Tag Archives: gold nanoparticles

Maybe spray-on technology can be used for heart repair?

Courtesy: University of Ottawa

That is a pretty stunning image and this March 15, 2022 news item on phys.org provides an explanation of what you see (Note: A link has been removed),

Could a spritz of super-tiny particles of gold and peptides on a damaged heart potentially provide minimally invasive, on-the-spot repair?

Cutting-edge research led by University of Ottawa Faculty of Medicine Associate Professors Dr. Emilio Alarcon and Dr. Erik Suuronen suggests a spray-on technology using customized nanoparticles of one of the world’s most precious metals offers tremendous therapeutic potential and could eventually help save many lives. Cardiovascular diseases are the leading cause of death globally, claiming roughly 18 million lives each year.

In a paper recently published online in ACS Nano, a peer-reviewed journal that highlighted the new research on its supplementary cover, Dr. Alarcon and his team of fellow investigators suggest that this approach might one day be used in conjunction with coronary artery bypass surgeries. That’s the most common type of heart surgery.

A March 15, 2021 University of Ottawa news release (also on EurekAlert) by David McFadden, which originated the news item, describes the research in more detail (Note: A link has been removed),

The therapy tested by the researchers – which was sprayed on the hearts of lab mice – used very low concentrations of peptide-modified particles of gold created in the laboratory. From the nozzle of a miniaturized spraying apparatus, the material can be evenly painted on the surface of a heart within a few seconds.

Gold nanoparticles have been shown to have some unusual properties and are highly chemically reactive. For years, researchers have been employing gold nanoparticles – so tiny they are undetectable by the human eye – in such a wide range of technologies that it’s become an area of intense research interest.

In this case, the custom-made nanogold modified with peptides—a short chain of amino acids —was sprayed on the hearts of lab mice. The research found that the spray-on therapy not only resulted in an increase in cardiac function and heart electrical conductivity but that there was no off-target organ infiltration by the tiny gold particles.

“That’s the beauty of this approach. You spray, then you wait a couple of weeks, and the animals are doing just fine compared to the controls,” says Dr. Alarcon, who is part of the Faculty of Medicine’s Department of Biochemistry, Microbiology and Immunology and also Director of the Bio-nanomaterials Chemistry and Engineering Laboratory at the University of the Ottawa Heart Institute.

Dr. Alarcon says that not only does the data suggest that the therapeutic action of the spray-on nanotherapeutic is highly effective, but its application is far simpler than other regenerative approaches for treating an infarcted heart.

At first, the observed improvement of cardiac function and electrical signal propagation in the hearts of tested mice was hard for the team to believe. But repeated experiments delivered the same positive results, according to Dr. Alarcon, who is part of the Faculty of Medicine’s Department of Biochemistry, Microbiology and Immunology and Director of the Bio-nanomaterials Chemistry and Engineering Laboratory at the University of Ottawa Heart Institute.

To validate the exciting findings in mice, the team is now seeking to adapt this technology to minimally invasive procedures that will expedite testing in large animal models, such as rabbits and pigs.

Dr. Alarcon praised the research culture at uOttawa and the Heart Institute, saying that the freedom to explore is paramount. “When you have an environment where you are allowed to make mistakes and criticize, that really drives discoveries,” he says.

The team involved in the paper includes researchers from uOttawa and the University of Talca in Chile. Part of the work was funded by the Canadian government’s New Frontiers in Research Fund, which was launched in 2018 and supports transformative high risk/high reward research led by Canadian researchers working with local and international partners.

Here’s a link to and a citation for the paper,

Nanoengineered Sprayable Therapy for Treating Myocardial Infarction by Marcelo Muñoz, Cagla Eren Cimenci, Keshav Goel, Maxime Comtois-Bona, Mahir Hossain, Christopher McTiernan, Matias Zuñiga-Bustos, Alex Ross, Brenda Truong, Darryl R. Davis, Wenbin Liang, Benjamin Rotstein, Marc Ruel, Horacio Poblete, Erik J. Suuronen, and Emilio I. Alarcon. ACS Nano 2022, 16, 3, 3522–3537 DOI: https://doi.org/10.1021/acsnano.1c08890 Publication Date: February 14, 2022 Copyright © 2022 The Authors. Published by American Chemical Society

This paper appears to be open access.

Mad, bad, and dangerous to know? Artificial Intelligence at the Vancouver (Canada) Art Gallery (1 of 2): The Objects

To my imaginary AI friend

Dear friend,

I thought you might be amused by these Roomba-like* paintbots at the Vancouver Art Gallery’s (VAG) latest exhibition, “The Imitation Game: Visual Culture in the Age of Artificial Intelligence” (March 5, 2022 – October 23, 2022).

Sougwen Chung, Omnia per Omnia, 2018, video (excerpt), Courtesy of the Artist

*A Roomba is a robot vacuum cleaner produced and sold by iRobot.

As far as I know, this is the Vancouver Art Gallery’s first art/science or art/technology exhibit and it is an alternately fascinating, exciting, and frustrating take on artificial intelligence and its impact on the visual arts. Curated by Bruce Grenville, VAG Senior Curator, and Glenn Entis, Guest Curator, the show features 20 ‘objects’ designed to both introduce viewers to the ‘imitation game’ and to challenge them. From the VAG Imitation Game webpage,

The Imitation Game surveys the extraordinary uses (and abuses) of artificial intelligence (AI) in the production of modern and contemporary visual culture around the world. The exhibition follows a chronological narrative that first examines the development of artificial intelligence, from the 1950s to the present [emphasis mine], through a precise historical lens. Building on this foundation, it emphasizes the explosive growth of AI across disciplines, including animation, architecture, art, fashion, graphic design, urban design and video games, over the past decade. Revolving around the important roles of machine learning and computer vision in AI research and experimentation, The Imitation Game reveals the complex nature of this new tool and demonstrates its importance for cultural production.

And now …

As you’ve probably guessed, my friend, you’ll find a combination of both background information and commentary on the show.

I’ve initially focused on two people (a scientist and a mathematician) who were seminal thinkers about machines, intelligence, creativity, and humanity. I’ve also provided some information about the curators, which hopefully gives you some insight into the show.

As for the show itself, you’ll find a few of the ‘objects’ highlighted with one of them being investigated at more length. The curators devoted some of the show to ethical and social justice issues, accordingly, the Vancouver Art Gallery hosted the University of British Columbia’s “Speculative Futures: Artificial Intelligence Symposium” on April 7, 2022,

Presented in conjunction with the exhibition The Imitation Game: Visual Culture in the Age of Artificial Intelligence, the Speculative Futures Symposium examines artificial intelligence and the specific uses of technology in its multifarious dimensions. Across four different panel conversations, leading thinkers of today will explore the ethical implications of technology and discuss how they are working to address these issues in cultural production.”

So, you’ll find more on these topics here too.

And for anyone else reading this (not you, my friend who is ‘strong’ AI and not similar to the ‘weak’ AI found in this show), there is a description of ‘weak’ and ‘strong’ AI on the avtsim.com/weak-ai-strong-ai webpage, Note: A link has been removed,

There are two types of AI: weak AI and strong AI.

Weak, sometimes called narrow, AI is less intelligent as it cannot work without human interaction and focuses on a more narrow, specific, or niched purpose. …

Strong AI on the other hand is in fact comparable to the fictitious AIs we see in media like the terminator. The theoretical Strong AI would be equivalent or greater to human intelligence.


My dear friend, I hope you will enjoy.

The Imitation Game and ‘mad, bad, and dangerous to know’

In some circles, it’s better known as ‘The Turing Test;” the Vancouver Art Gallery’s ‘Imitation Game’ hosts a copy of Alan Turing’s foundational paper for establishing whether artificial intelligence is possible (I thought this was pretty exciting).

Here’s more from The Turing Test essay by Graham Oppy and David Dowe for the Stanford Encyclopedia of Philosophy,

The phrase “The Turing Test” is most properly used to refer to a proposal made by Turing (1950) as a way of dealing with the question whether machines can think. According to Turing, the question whether machines can think is itself “too meaningless” to deserve discussion (442). However, if we consider the more precise—and somehow related—question whether a digital computer can do well in a certain kind of game that Turing describes (“The Imitation Game”), then—at least in Turing’s eyes—we do have a question that admits of precise discussion. Moreover, as we shall see, Turing himself thought that it would not be too long before we did have digital computers that could “do well” in the Imitation Game.

The phrase “The Turing Test” is sometimes used more generally to refer to some kinds of behavioural tests for the presence of mind, or thought, or intelligence in putatively minded entities. …

Next to the display holding Turing’s paper, is another display with an excerpt of an explanation from Turing about how he believed Ada Lovelace would have responded to the idea that machines could think based on a copy of some of her writing (also on display). She proposed that creativity, not thinking, is what set people apart from machines. (See the April 17, 2020 article “Thinking Machines? Has the Lovelace Test Been Passed?’ on mindmatters.ai.)

It’s like a dialogue between two seminal thinkers who lived about 100 years apart; Lovelace, born in 1815 and dead in 1852, and Turing, born in 1912 and dead in 1954. Both have fascinating back stories (more about those later) and both played roles in how computers and artificial intelligence are viewed.

Adding some interest to this walk down memory lane is a 3rd display, an illustration of the ‘Mechanical Turk‘, a chess playing machine that made the rounds in Europe from 1770 until it was destroyed in 1854. A hoax that fooled people for quite a while it is a reminder that we’ve been interested in intelligent machines for centuries. (Friend, Turing and Lovelace and the Mechanical Turk are found in Pod 1.)

Back story: Turing and the apple

Turing is credited with being instrumental in breaking the German ENIGMA code during World War II and helping to end the war. I find it odd that he ended up at the University of Manchester in the post-war years. One would expect him to have been at Oxford or Cambridge. At any rate, he died in 1954 of cyanide poisoning two years after he was arrested for being homosexual and convicted of indecency. Given the choice of incarceration or chemical castration, he chose the latter. There is, to this day, debate about whether or not it was suicide. Here’s how his death is described in this Wikipedia entry (Note: Links have been removed),

On 8 June 1954, at his house at 43 Adlington Road, Wilmslow,[150] Turing’s housekeeper found him dead. He had died the previous day at the age of 41. Cyanide poisoning was established as the cause of death.[151] When his body was discovered, an apple lay half-eaten beside his bed, and although the apple was not tested for cyanide,[152] it was speculated that this was the means by which Turing had consumed a fatal dose. An inquest determined that he had committed suicide. Andrew Hodges and another biographer, David Leavitt, have both speculated that Turing was re-enacting a scene from the Walt Disney film Snow White and the Seven Dwarfs (1937), his favourite fairy tale. Both men noted that (in Leavitt’s words) he took “an especially keen pleasure in the scene where the Wicked Queen immerses her apple in the poisonous brew”.[153] Turing’s remains were cremated at Woking Crematorium on 12 June 1954,[154] and his ashes were scattered in the gardens of the crematorium, just as his father’s had been.[155]

Philosopher Jack Copeland has questioned various aspects of the coroner’s historical verdict. He suggested an alternative explanation for the cause of Turing’s death: the accidental inhalation of cyanide fumes from an apparatus used to electroplate gold onto spoons. The potassium cyanide was used to dissolve the gold. Turing had such an apparatus set up in his tiny spare room. Copeland noted that the autopsy findings were more consistent with inhalation than with ingestion of the poison. Turing also habitually ate an apple before going to bed, and it was not unusual for the apple to be discarded half-eaten.[156] Furthermore, Turing had reportedly borne his legal setbacks and hormone treatment (which had been discontinued a year previously) “with good humour” and had shown no sign of despondency prior to his death. He even set down a list of tasks that he intended to complete upon returning to his office after the holiday weekend.[156] Turing’s mother believed that the ingestion was accidental, resulting from her son’s careless storage of laboratory chemicals.[157] Biographer Andrew Hodges theorised that Turing arranged the delivery of the equipment to deliberately allow his mother plausible deniability with regard to any suicide claims.[158]

The US Central Intelligence Agency (CIA) also has an entry for Alan Turing dated April 10, 2015 it’s titled, The Enigma of Alan Turing.

Back story: Ada Byron Lovelace, the 2nd generation of ‘mad, bad, and dangerous to know’

A mathematician and genius in her own right, Ada Lovelace’s father George Gordon Byron, better known as the poet Lord Byron, was notoriously described as ‘mad, bad, and dangerous to know’.

Lovelace too could have been been ‘mad, bad, …’ but she is described less memorably as “… manipulative and aggressive, a drug addict, a gambler and an adulteress, …” as mentioned in my October 13, 20215 posting. It marked the 200th anniversary of her birth, which was celebrated with a British Broadcasting Corporation (BBC) documentary and an exhibit at the Science Museum in London, UK.

She belongs in the Vancouver Art Gallery’s show along with Alan Turing due to her prediction that computers could be made to create music. She also published the first computer program. Her feat is astonishing when you know only one working model {1/7th of the proposed final size) of a computer was ever produced. (The machine invented by Charles Babbage was known as a difference engine. You can find out more about the Difference engine on Wikipedia and about Babbage’s proposed second invention, the Analytical engine.)

(Byron had almost nothing to do with his daughter although his reputation seems to have dogged her. You can find out more about Lord Byron here.)

AI and visual culture at the VAG: the curators

As mentioned earlier, the VAG’s “The Imitation Game: Visual Culture in the Age of Artificial Intelligence” show runs from March 5, 2022 – October 23, 2022. Twice now, I have been to this weirdly exciting and frustrating show.

Bruce Grenville, VAG Chief/Senior Curator, seems to specialize in pulling together diverse materials to illustrate ‘big’ topics. His profile for Emily Carr University of Art + Design (where Grenville teaches) mentions these shows ,

… He has organized many thematic group exhibitions including, MashUp: The Birth of Modern Culture [emphasis mine], a massive survey documenting the emergence of a mode of creativity that materialized in the late 1800s and has grown to become the dominant model of cultural production in the 21st century; KRAZY! The Delirious World [emphasis mine] of Anime + Manga + Video Games + Art, a timely and important survey of modern and contemporary visual culture from around the world; Home and Away: Crossing Cultures on the Pacific Rim [emphasis mine] a look at the work of six artists from Vancouver, Beijing, Ho Chi Minh City, Seoul and Los Angeles, who share a history of emigration and diaspora. …

Glenn Entis, Guest Curator and founding faculty member of Vancouver’s Centre for Digital Media (CDM) is Grenville’s co-curator, from Entis’ CDM profile,

“… an Academy Award-winning animation pioneer and games industry veteran. The former CEO of Dreamworks Interactive, Glenn worked with Steven Spielberg and Jeffrey Katzenberg on a number of video games …,”

Steve Newton in his March 4, 2022 preview does a good job of describing the show although I strongly disagree with the title of his article which proclaims “The Vancouver Art Gallery takes a deep dive into artificial intelligence with The Imitation Game.” I think it’s more of a shallow dive meant to cover more distance than depth,

… The exhibition kicks off with an interactive introduction inviting visitors to actively identify diverse areas of cultural production influenced by AI.

“That was actually one of the pieces that we produced in collaboration with the Centre for Digital Media,” Grenville notes, “so we worked with some graduate-student teams that had actually helped us to design that software. It was the beginning of COVID when we started to design this, so we actually wanted a no-touch interactive. So, really, the idea was to say, ‘Okay, this is the very entrance to the exhibition, and artificial intelligence, this is something I’ve heard about, but I’m not really sure how it’s utilized in ways. But maybe I know something about architecture; maybe I know something about video games; maybe I know something about the history of film.

“So you point to these 10 categories of visual culture [emphasis mine]–video games, architecture, fashion design, graphic design, industrial design, urban design–so you point to one of those, and you might point to ‘film’, and then when you point at it that opens up into five different examples of what’s in the show, so it could be 2001: A Space Odyssey, or Bladerunner, or World on a Wire.”

After the exhibition’s introduction—which Grenville equates to “opening the door to your curiosity” about artificial intelligence–visitors encounter one of its main categories, Objects of Wonder, which speaks to the history of AI and the critical advances the technology has made over the years.

“So there are 20 Objects of Wonder [emphasis mine],” Grenville says, “which go from 1949 to 2022, and they kind of plot out the history of artificial intelligence over that period of time, focusing on a specific object. Like [mathematician and philosopher] Norbert Wiener made this cybernetic creature, he called it a ‘Moth’, in 1949. So there’s a section that looks at this idea of kind of using animals–well, machine animals–and thinking about cybernetics, this idea of communication as feedback, early thinking around neuroscience and how neuroscience starts to imagine this idea of a thinking machine.

And there’s this from Newton’s March 4, 2022 preview,

“It’s interesting,” Grenville ponders, “artificial intelligence is virtually unregulated. [emphasis mine] You know, if you think about the regulatory bodies that govern TV or radio or all the types of telecommunications, there’s no equivalent for artificial intelligence, which really doesn’t make any sense. And so what happens is, sometimes with the best intentions [emphasis mine]—sometimes not with the best intentions—choices are made about how artificial intelligence develops. So one of the big ones is facial-recognition software [emphasis mine], and any body-detection software that’s being utilized.

In addition to it being the best overview of the show I’ve seen so far, this is the only one where you get a little insight into what the curators were thinking when they were developing it.

A deep dive into AI?

it was only while searching for a little information before the show that I realized I don’t have any definitions for artificial intelligence! What is AI? Sadly, there are no definitions of AI in the exhibit.

It seems even experts don’t have a good definition. Take a look at this,

The definition of AI is fluid [emphasis mine] and reflects a constantly shifting landscape marked by technological advancements and growing areas of application. Indeed, it has frequently been observed that once AI becomes capable of solving a particular problem or accomplishing a certain task, it is often no longer considered to be “real” intelligence [emphasis mine] (Haenlein & Kaplan, 2019). A firm definition was not applied for this report [emphasis mine], given the variety of implementations described above. However, for the purposes of deliberation, the Panel chose to interpret AI as a collection of statistical and software techniques, as well as the associated data and the social context in which they evolve — this allows for a broader and more inclusive interpretation of AI technologies and forms of agency. The Panel uses the term AI interchangeably to describe various implementations of machine-assisted design and discovery, including those based on machine learning, deep learning, and reinforcement learning, except for specific examples where the choice of implementation is salient. [p. 6 print version; p. 34 PDF version]

The above is from the Leaps and Boundaries report released May 10, 2022 by the Council of Canadian Academies’ Expert Panel on Artificial Intelligence for Science and Engineering.

Sometimes a show will take you in an unexpected direction. I feel a lot better ‘not knowing’. Still, I wish the curators had acknowledged somewhere in the show that artificial intelligence is a slippery concept. Especially when you add in robots and automatons. (more about them later)

21st century technology in a 19th/20th century building

Void stairs inside the building. Completed in 1906, the building was later designated as a National Historic Site in 1980 [downloaded from https://en.wikipedia.org/wiki/Vancouver_Art_Gallery#cite_note-canen-7]

Just barely making it into the 20th century, the building where the Vancouver Art Gallery currently resides was for many years the provincial courthouse (1911 – 1978). In some ways, it’s a disconcerting setting for this show.

They’ve done their best to make the upstairs where the exhibit is displayed look like today’s galleries with their ‘white cube aesthetic’ and strong resemblance to the scientific laboratories seen in movies.

(For more about the dominance, since the 1930s, of the ‘white cube aesthetic’ in art galleries around the world, see my July 26, 2021 posting; scroll down about 50% of the way.)

It makes for an interesting tension, the contrast between the grand staircase, the cupola, and other architectural elements and the sterile, ‘laboratory’ environment of the modern art gallery.

20 Objects of Wonder and the flow of the show

It was flummoxing. Where are the 20 objects? Why does it feel like a maze in a laboratory? Loved the bees, but why? Eeeek Creepers! What is visual culture anyway? Where am I?

The objects of the show

It turns out that the curators have a more refined concept for ‘object’ than I do. There weren’t 20 material objects, there were 20 numbered ‘pods’ with perhaps a screen or a couple of screens or a screen and a material object or two illustrating the pod’s topic.

Looking up a definition for the word (accessed from a June 9, 2022 duckduckgo.com search). yielded this, (the second one seems à propos),

objectŏb′jĭkt, -jĕkt″


1. Something perceptible by one or more of the senses, especially by vision or touch; a material thing.

2. A focus of attention, feeling, thought, or action.

3. A limiting factor that must be considered.

The American Heritage® Dictionary of the English Language, 5th Edition.

Each pod = a focus of attention.

The show’s flow is a maze. Am I a rat?

The pods are defined by a number and by temporary walls. So if you look up, you’ll see a number and a space partly enclosed by a temporary wall or two.

It’s a very choppy experience. For example, one minute you can be in pod 1 and, when you turn the corner, you’re in pod 4 or 5 or ? There are pods I’ve not seen, despite my two visits, because I kept losing my way. This led to an existential crisis on my second visit. “Had I missed the greater meaning of this show? Was there some sort of logic to how it was organized? Was there meaning to my life? Was I a rat being nudged around in a maze?” I didn’t know.

Thankfully, I have since recovered. But, I will return to my existential crisis later, with a special mention for “Creepers.”

The fascinating

My friend, you know I appreciated the history and in addition to Alan Turing, Ada Lovelace and the Mechanical Turk, at the beginning of the show, they included a reference to Ovid (or Pūblius Ovidius Nāsō), a Roman poet who lived from 43 BCE – 17/18 CE in one of the double digit (17? or 10? or …) in one of the pods featuring a robot on screen. As to why Ovid might be included, this excerpt from a February 12, 2018 posting on the cosmolocal.org website provides a clue (Note. Links have been removed),

The University of King’s College [Halifax, Nova Scotia] presents Automatons! From Ovid to AI, a nine-lecture series examining the history, issues and relationships between humans, robots, and artificial intelligence [emphasis mine]. The series runs from January 10 to April 4 [2018], and features leading scholars, performers and critics from Canada, the US and Britain.

“Drawing from theatre, literature, art, science and philosophy, our 2018 King’s College Lecture Series features leading international authorities exploring our intimate relationships with machines,” says Dr. Gordon McOuat, professor in the King’s History of Science and Technology (HOST) and Contemporary Studies Programs.

“From the myths of Ovid [emphasis mine] and the automatons [emphasis mine] of the early modern period to the rise of robots, cyborgs, AI and artificial living things in the modern world, the 2018 King’s College Lecture Series examines the historical, cultural, scientific and philosophical place of automatons in our lives—and our future,” adds McOuat.

I loved the way the curators managed to integrate the historical roots for artificial intelligence and, by extension, the world of automatons, robots, cyborgs, and androids. Yes, starting the show with Alan Turing and Ada Lovelace could be expected but Norbert Wiener’s Moth (1949) acts as a sort of preview for Sougwen Chung’s “Omnia per Omnia, 2018” (GIF seen at the beginning of this post). Take a look for yourself (from the cyberneticzoo.com September 19, 2009 posting by cyberne1. Do you see the similarity or am I the only one?

[sourced from Google images, Source:life) & downloaded from https://cyberneticzoo.com/cyberneticanimals/1949-wieners-moth-wiener-wiesner-singleton/]


This is the first time I’ve come across an AI/sculpture project. The VAG show features Scott Eaton’s sculptures on screens in a room devoted to his work.

Scott Eaton: Entangled II, 2019 4k video (still) Courtesy of the Artist [downloaded from https://www.vanartgallery.bc.ca/exhibitions/the-imitation-game]

This looks like an image of a piece of ginger root and It’s fascinating to watch the process as the AI agent ‘evolves’ Eaton’s drawings into onscreen sculptures. It would have enhanced the experience if at least one of Eaton’s ‘evolved’ and physically realized sculptures had been present in the room but perhaps there were financial and/or logistical reasons for the absence.

Both Chung and Eaton are collaborating with an AI agent. In Chung’s case the AI is integrated into the paintbots with which she interacts and paints alongside and in Eaton’s case, it’s via a computer screen. In both cases, the work is mildly hypnotizing in a way that reminds me of lava lamps.

One last note about Chung and her work. She was one of the artists invited to present new work at an invite-only April 22, 2022 Embodied Futures workshop at the “What will life become?” event held by the Berrgruen Institute and the University of Southern California (USC),

Embodied Futures invites participants to imagine novel forms of life, mind, and being through artistic and intellectual provocations on April 22 [2022].

Beginning at 1 p.m., together we will experience the launch of five artworks commissioned by the Berggruen Institute. We asked these artists: How does your work inflect how we think about “the human” in relation to alternative “embodiments” such as machines, AIs, plants, animals, the planet, and possible alien life forms in the cosmos? [emphases mine]  Later in the afternoon, we will take provocations generated by the morning’s panels and the art premieres in small breakout groups that will sketch futures worlds, and lively entities that might dwell there, in 2049.

This leads to (and my friend, while I too am taking a shallow dive, for this bit I’m going a little deeper):

Bees and architecture

Neri Oxman’s contribution (Golden Bee Cube, Synthetic Apiary II [2020]) is an exhibit featuring three honeycomb structures and a video featuring the bees in her synthetic apiary.

Neri Oxman and the MIT Mediated Matter Group, Golden Bee Cube, Synthetic Apiary II, 2020, beeswax, acrylic, gold particles, gold powder Courtesy of Neri Oxman and the MIT Mediated Matter Group

Neri Oxman (then a faculty member of the Mediated Matter Group at the Massachusetts Institute of Technology) described the basis for the first and all other iterations of her synthetic apiary in Patrick Lynch’s October 5, 2016 article for ‘ArchDaily; Broadcasting Architecture Worldwide’, Note: Links have been removed,

Designer and architect Neri Oxman and the Mediated Matter group have announced their latest design project: the Synthetic Apiary. Aimed at combating the massive bee colony losses that have occurred in recent years, the Synthetic Apiary explores the possibility of constructing controlled, indoor environments that would allow honeybee populations to thrive year-round.

“It is time that the inclusion of apiaries—natural or synthetic—for this “keystone species” be considered a basic requirement of any sustainability program,” says Oxman.

In developing the Synthetic Apiary, Mediated Matter studied the habits and needs of honeybees, determining the precise amounts of light, humidity and temperature required to simulate a perpetual spring environment. [emphasis mine] They then engineered an undisturbed space where bees are provided with synthetic pollen and sugared water and could be evaluated regularly for health.

In the initial experiment, the honeybees’ natural cycle proved to adapt to the new environment, as the Queen was able to successfully lay eggs in the apiary. The bees showed the ability to function normally in the environment, suggesting that natural cultivation in artificial spaces may be possible across scales, “from organism- to building-scale.”

“At the core of this project is the creation of an entirely synthetic environment enabling controlled, large-scale investigations of hives,” explain the designers.

Mediated Matter chose to research into honeybees not just because of their recent loss of habitat, but also because of their ability to work together to create their own architecture, [emphasis mine] a topic the group has explored in their ongoing research on biologically augmented digital fabrication, including employing silkworms to create objects and environments at product, architectural, and possibly urban, scales.

“The Synthetic Apiary bridges the organism- and building-scale by exploring a “keystone species”: bees. Many insect communities present collective behavior known as “swarming,” prioritizing group over individual survival, while constantly working to achieve common goals. Often, groups of these eusocial organisms leverage collaborative behavior for relatively large-scale construction. For example, ants create extremely complex networks by tunneling, wasps generate intricate paper nests with materials sourced from local areas, and bees deposit wax to build intricate hive structures.”

This January 19, 2022 article by Crown Honey for its eponymous blog updates Oxman’s work (Note 1: All emphases are mine; Note 2: A link has been removed),

Synthetic Apiary II investigates co-fabrication between humans and honey bees through the use of designed environments in which Apis mellifera colonies construct comb. These designed environments serve as a means by which to convey information to the colony. The comb that the bees construct within these environments comprises their response to the input information, enabling a form of communication through which we can begin to understand the hive’s collective actions from their perspective.

Some environments are embedded with chemical cues created through a novel pheromone 3D-printing process, while others generate magnetic fields of varying strength and direction. Others still contain geometries of varying complexity or designs that alter their form over time.

When offered wax augmented with synthetic biomarkers, bees appear to readily incorporate it into their construction process, likely due to the high energy cost of producing fresh wax. This suggests that comb construction is a responsive and dynamic process involving complex adaptations to perturbations from environmental stimuli, not merely a set of predefined behaviors building toward specific constructed forms. Each environment therefore acts as a signal that can be sent to the colony to initiate a process of co-fabrication.

Characterization of constructed comb morphology generally involves visual observation and physical measurements of structural features—methods which are limited in scale of analysis and blind to internal architecture. In contrast, the wax structures built by the colonies in Synthetic Apiary II are analyzed through high-throughput X-ray computed tomography (CT) scans that enable a more holistic digital reconstruction of the hive’s structure.

Geometric analysis of these forms provides information about the hive’s design process, preferences, and limitations when tied to the inputs, and thereby yields insights into the invisible mediations between bees and their environment.
Developing computational tools to learn from bees can facilitate the very beginnings of a dialogue with them. Refined by evolution over hundreds of thousands of years, their comb-building behaviors and social organizations may reveal new forms and methods of formation that can be applied across our human endeavors in architecture, design, engineering, and culture.

Further, with a basic understanding and language established, methods of co-fabrication together with bees may be developed, enabling the use of new biocompatible materials and the creation of more efficient structural geometries that modern technology alone cannot achieve.

In this way, we also move our built environment toward a more synergistic embodiment, able to be more seamlessly integrated into natural environments through material and form, even providing habitats of benefit to both humans and nonhumans. It is essential to our mutual survival for us to not only protect but moreover to empower these critical pollinators – whose intrinsic behaviors and ecosystems we have altered through our industrial processes and practices of human-centric design – to thrive without human intervention once again.

In order to design our way out of the environmental crisis that we ourselves created, we must first learn to speak nature’s language. …

The three (natural, gold nanoparticle, and silver nanoparticle) honeycombs in the exhibit are among the few physical objects (the others being the historical documents and the paintbots with their canvasses) in the show and it’s almost a relief after the parade of screens. It’s the accompanying video that’s eerie. Everything is in white, as befits a science laboratory, in this synthetic apiary where bees are fed sugar water and fooled into a spring that is eternal.

Courtesy: Massachusetts Institute of Technology Copyright: Mediated Matter [downloaded from https://www.media.mit.edu/projects/synthetic-apiary/overview/]

(You may want to check out Lynch’s October 5, 2016 article or Crown Honey’s January 19, 2022 article as both have embedded images and the Lynch article includes a Synthetic Apiary video. The image above is a still from the video.)

As I asked a friend, where are the flowers? Ron Miksha, a bee ecologist working at the University of Calgary, details some of the problems with Oxman’s Synthetic Apiary this way in his October 7, 2016 posting on his Bad Beekeeping Blog,

In a practical sense, the synthetic apiary fails on many fronts: Bees will survive a few months on concoctions of sugar syrup and substitute pollen, but they need a natural variety of amino acids and minerals to actually thrive. They need propolis and floral pollen. They need a ceiling 100 metres high and a 2-kilometre hallway if drone and queen will mate, or they’ll die after the old queen dies. They need an artificial sun that travels across the sky, otherwise, the bees will be attracted to artificial lights and won’t return to their hive. They need flowery meadows, fresh water, open skies. [emphasis mine] They need a better holodeck.

Dorothy Woodend’s March 10, 2022 review of the VAG show for The Tyee poses other issues with the bees and the honeycombs,

When AI messes about with other species, there is something even more unsettling about the process. American-Israeli artist Neri Oxman’s Golden Bee Cube, Synthetic Apiary II, 2020 uses real bees who are proffered silver and gold [nanoparticles] to create their comb structures. While the resulting hives are indeed beautiful, rendered in shades of burnished metal, there is a quality of unease imbued in them. Is the piece akin to apiary torture chambers? I wonder how the bees feel about this collaboration and whether they’d like to renegotiate the deal.

There’s no question the honeycombs are fascinating and disturbing but I don’t understand how artificial intelligence was a key factor in either version of Oxman’s synthetic apiary. In the 2022 article by Crown Honey, there’s this “Developing computational tools to learn from bees can facilitate the very beginnings of a dialogue with them [honeybees].” It’s probable that the computational tools being referenced include AI and the Crown Honey article seems to suggest those computational tools are being used to analyze the bees behaviour after the fact.

Yes, I can imagine a future where ‘strong’ AI (such as you, my friend) is in ‘dialogue’ with the bees and making suggestions and running the experiments but it’s not clear that this is the case currently. The Oxman exhibit contribution would seem to be about the future and its possibilities whereas many of the other ‘objects’ concern the past and/or the present.

Friend, let’s take a break, shall we? Part 2 is coming up.

Using natural proteins to grow gold nanoclusters for hybrid bionanomaterials

While there’s a January 10, 2022 news item on Nanowerk, the research being announced was made available online in the Fall of 2021 and is now available in print,

Gold nanoclusters are groups of a few gold atoms with interesting photoluminescent properties. The features of gold nanoclusters depend not only on their structure, but their size and also by the ligands coordinated to them. These inorganic nanomaterials have been used in sensing, biomedicine and optics and their coordination with biomolecules can endow multiple capabilities in biological media.

A research collaboration between the groups of Dr. Juan Cabanillas, Research Professor at IMDEA Nanociencia and Dr. Aitziber L. Cortajarena, Ikerbasque Professor and Principal Investigator at CIC biomaGUNE have explored the use of natural proteins to grow gold nanoclusters, resulting in hybrid bionanomaterials with tunable photoluminescent properties and with a plethora of potential applications.

A January 10, 2022 IMDEA Nanociencia press release, which originated the news item, provides more technical detail about the research,

The nanoclusters –with less than 2 nm in size- differentiate from larger nanoparticles (plasmonic) since they present discrete energy levels coupled optically. The groups of amino acids within the proteins coordinate the gold atoms and allow the groups to be arranged around the gold nanocluster, facilitating the stabilization and adding an extra level of tailoring. These nanoclusters have interesting energy harvesting features. Since the discrete energy levels are optically coupled, the absorption of a photon leads to promotion of an electron to higher levels, which can trigger a photophysical process or a photochemical reaction.  

The results by Cabanillas and Cortajarena groups, published in Advanced Optical Materials and Nano Letters, explore the origin of the photoluminescence in protein-designed gold nanoclusters and shed light into the strong influence of environmental conditions on the nature of luminescence. Nanocluster capping by two types of amino acids (histidine and cysteine) allow for changing the emission spectral range from blue to red, paving the way to tune the optical properties by an appropriate ligand choice. The nature of emission is also changed with capping, from fluorescence to phosphorescence, respectively. The synergistic protein-nanocluster effects on emission are still not clear, and the groups at IMDEA Nanociencia and CIC biomaGUNE are working to elucidate the mechanisms behind. There are potential applications for the aforementioned nanoclusters, in solid state as active medium in laser cavities. Optical gain properties from these nanoclusters are yet to be demonstrated, which could pave the way to a new generation of potentially interesting laser devices. As the combination of gold plus proteins is potentially biocompatible, many potential applications in biomedicine can also be envisaged.

A related publication of the groups in Nano Letters demonstrates that the insertion of tryptophans, amino acids with high electron density, in the vicinity of the nanocluster boosts its photoluminescence quantum efficiency up to 40% in some cases, values relevant for solid state light emission applications. Researchers also observed an antenna effect: the tryptophans can absorb light in a discrete manner and transfer the energy to the cluster. This effect has interest for energy harvesting and for sensing purposes as well.

The proteins through the biocapping enable the synthesis of the nanoclusters and largely improve their quantum efficiency. “The photoluminescence quantum efficiency is largely improved when using the biocapping” Dr. Cabanillas says. He believes this research work means “a new field opening for the tuning of optical properties of nanoclusters through protein engineering, and much work is ahead for the understanding of the amplification mechanism”. Dr. Cortajarena emphasizes “we have already demonstrated the great potential of engineered photoluminescent protein-nanocluster in biomedical and technological fields, and understanding the fundamental emission mechanisms is pivotal for future applications“. A variety of further applications include biosensors, as the protein admits functionalization with recognition molecules, energy harvesting, imaging and photodynamic therapies. Further work is ahead this opening avenue for photophysics research.

This research is a collaboration led by Dr. Juan Cabanillas and Dr. Aitziber L. Cortajarena research groups at IMDEA Nanociencia and CIC biomaGUNE, with contributions from researchers at the Diamond Light Source Ltd. [synchrotron] and DIPC. It has been cofounded by the projects AMAPOLA, NMAT2D, FULMATEN, Atracción de Talento from Comunidad de Madrid and the Severo Ochoa Centre of Excellence award to IMDEA Nanociencia. CIC biomaGUNE acknowledges support by the projects ERC-ProNANO, ERC-NIMM, ProTOOLs and the Maria de Maeztu Units of Excellence Programme.

Here are links to and citations for the papers,

Tuning the Optical Properties of Au Nanoclusters by Designed Proteins by Elena Lopez-Martinez, Diego Gianolio, Saül Garcia-Orrit, Victor Vega-Mayoral, Juan Cabanillas-Gonzalez, Carlos Sanchez-Cano, Aitziber L. Cortajarena. Advanced Optical Materials Volume 10, Issue 1 January 4, 2022 2101332 DOI: https://doi.org/10.1002/adom.202101332 First published: 31 October 2021

This paper is open access.

Boosting the Photoluminescent Properties of Protein-Stabilized Gold Nanoclusters through Protein Engineering by Antonio Aires, Ahmad Sousaraei, Marco Möller, Juan Cabanillas-Gonzalez, and Aitziber L. Cortajarena. Nano Lett. 2021, 21, 21, 9347–9353 DOI: https://doi.org/10.1021/acs.nanolett.1c03768 Publication Date: November 1, 2021 Copyright © 2021 American Chemical Society

This paper is behind a paywall.

Not being familiar with either of the two research institutions mentioned in the press release, I did a little digging.

Here’s a little information about IMDEA Nanociencia (IMDEA Nanoscience Institute), from its Wikipedia entry, Note: All links have been removed,

IMDEA Nanoscience Institute is a private non-profit foundation within the IMDEA Institutes network, created in 2006-2007 as a result of collaboration agreement between the Community of Madrid and Spanish Ministry of Education and Science. The foundation manages IMDEA-Nanoscience Institute,[1] a scientific centre dedicated to front-line research in nanoscience, nanotechnology and molecular design and aiming at transferable innovations and close contact with industries. IMDEA Nanoscience is a member of the Campus of International excellence, a consortium of research institutes promoted by the Autonomous University of Madrid and Spanish National Research Council (UAM/CSIC).[2]

As for CIC biomaGUNE, here’s more from its institutional profile on the science.eus website,

The Centre for Cooperative Research in Biomaterials-CIC biomaGUNE, located in San Sebastian (Spain), was officially opened in December 2006. CIC biomaGUNE is a non-profit research organization created to promote scientific research and technological innovation at the highest levels in the Basque Country following the BioBasque policy in order to create a new business sector based on biosciences. Established by the Department of Industry, Technology & Innovation of the Government of the Autonomous Community of the Basque Country, CIC biomaGUNE constitutes one of the Centres of the CIC network, the largest Basque Country research network on specific strategic areas, having the mission to contribute to the economical and social development of the country through the generation of knowledge and speeding up the process that leads to technological innovation.

‘Playing telephone’ with multivalent gold nanoparticles

A July 7, 2021 news item on phys.org describes what ‘playing telephone’ has to do with gold nanoparticles,

Cells play a precise game of telephone, sending messages to each other that trigger actions further on. With clear signaling, the cells achieve their goals. In disease, however, the signals break up and result in confused messaging and unintended consequences. To help parse out these signals and how they function in health—and go awry in disease—scientists tag proteins with labels they can follow as the proteins interact with the molecular world around them.

The challenge is figuring out which proteins to label in the first place. Now, a team led by researchers from Tokyo University of Agriculture and Technology (TUAT) has developed a new approach to identifying and tagging the specific proteins. They published their results on June 1 [2021] in Angewandte Chemie.

A July 8, 2021 TUAT press release on EurekAlert, which originated the news item, delves further into the research (I appreciate how clearly the work is explained),

“We are interested in exploring protein receptors of certain carbohydrate molecules that are involved in mediating cell signaling, particularly in cancer cells,” said paper author Kaori Sakurai, associate professor in the Department of Biotechnology and Life Science at TUAT.

The carbohydrate molecules, called ligands, are typically expressed on the surface of cells and are known to dynamically form complexes with protein receptors to coordinate complicated cellular functions. However, Sakurai said, the proteins responsible for binding the carbohydrates have been difficult to identify because they bond so weakly with the molecules.

The researchers designed a new type of carbohydrate probe that would not only link to the molecules, but tightly bind to them.

“We used gold nanoparticles as a scaffold to attach both carbohydrate ligands and electrophiles — a chemical that loves to react with other molecules — in a multivalent fashion,” Sakurai said. “This way, we were able to greatly increase binding affinity and reaction efficiency toward carbohydrate-binding proteins.”

The researchers applied the designed probes to cell lysate, a fluid containing the innards of broken-apart cells.

“The probes quickly found the target carbohydrate-binding proteins, triggering the electrophilic groups to react with electron-donating amino acid residues on nearby proteins,” Sakurai said. “This resulted in proteins firmly cross-linked to the gold nanoparticles’ surface, making it easy to subsequently analyze their identities.”

The team evaluated several electrophilic groups to identify the most efficient type for labeling their target proteins.

“We found that a particular electrophilic group called aryl sulfonyl fluoride is best suited for affinity labeling of carbohydrate-binding proteins,” said co-author Nanako Suto, a graduate student in the Department of Biotechnology and Life Science of TUAT. “However, they have rarely been used to identify target proteins, presumably because they would non-selectively react with various other, undesired proteins.”

However, the scale of aryl sulfonyl fluoride use appears to mitigate the issue.

“The non-selectivity isn’t a problem if aryl sulfonyl fluoride is used at very low concentrations, at the range of the nanoscale,” said co-author Shione Kamoshita, also a graduate student in the Department of Biotechnology and Life Science, TUAT.

The gold nanoparticle scaffolding displays many copies of the electrophilic group, which keeps aryl sulfonyl fluoride’s local concentration high on the nanoparticle surface but restrains them from the general cell system and reacting to undesired proteins. With the high concentration at the nano-level, some copies of electrophilic groups can efficiently react with target proteins.

“Through this process, we were able to achieve highly efficient and selective affinity labeling of carbohydrate-binding proteins in cell lysate,” Sakurai said. “We will apply the new method in target identification of several cancer-related carbohydrate ligands and investigate their function in cancer development. In parallel, we aim to explore the general utility of this new probe design for various other bioactive small molecules, so that we can accelerate the elucidation of their mechanisms.”

Here’s a link to and a citation for the paper,

Exploration of the Reactivity of Multivalent Electrophiles for Affinity Labeling: Sulfonyl Fluoride as a Highly Efficient and Selective Label by Nanako Suto, Shione Kamoshita, Dr. Shoichi Hosoya, Prof. Kaori Sakurai. Angewandte Chemie Volume 60, Issue 31 July 26, 2021 Pages 17080-17087 DOI: https://doi.org/10.1002/anie.202104347 First published: 01 June 2021

This paper is behind a paywall.

Joint Mexican/Finnish research team analyzes circulating currents inside gold nanoparticles

An April 30, 2021 news item on ScienceDaily announces the research,

Researchers in the Nanoscience Center of University of Jyvaskyla, in Finland and in the Guadalajara University in Mexico developed a method that allows for simulation and visualization of magnetic-field-induced electron currents inside gold nanoparticles. The method facilitates accurate analysis of magnetic field effects inside complex nanostructures in nuclear magnetic resonance measurements and establishes quantitative criteria for aromaticity of nanoparticles. The work was published 30.4.2021 as an Open Access article in Nature Communications.

An April 30, 2021 University of Jyväskylä – Jyväskylän yliopisto news release (also on EurekAlert), which originated the news item, describes the work in greater technical detail,

According to the classical electromagnetism, a charged particle moving in an external magnetic field experiences a force that makes the particle’s path circular. This basic law of physics is used, e.g., in designing cyclotrons that work as particle accelerators. When nanometer-size metal particles are placed in a magnetic field, the field induces a circulating electron current inside the particle. The circulating current in turn creates an internal magnetic field that opposes the external field. This physical effect is called magnetic shielding.

The strength of the shielding can be investigated by using nuclear magnetic resonance (NMR) spectroscopy. The internal magnetic shielding varies strongly in an atomic length scale even inside a nanometer-size particle. Understanding these atom-scale variations is possible only by employing quantum mechanical theory of the electronic properties of each atom making the nanoparticle.

Now, the research group of Professor Hannu Häkkinen in the University of Jyväskylä, in collaboration with University of Guadalajara in Mexico, developed a method to compute, visualize, and analyze the circulating electron currents inside complex 3D nanostructures. The method was applied to gold nanoparticles with a diameter of only about one nanometer. The calculations shed light onto unexplained experimental results from previous NMR measurements in the literature regarding how magnetic shielding inside the particle changes when one gold atom is replaced by one platinum atom.

A new quantitative measure to characterize aromaticity inside metal nanoparticles was also developed based on the total integrated strength of the shielding electron current.

“Aromaticity of molecules is one of the oldest concepts in chemistry, and it has been traditionally connected to ring-like organic molecules and to their delocalized valence electron density that can develop circulating currents in an external magnetic field. However, generally accepted quantitative criteria for the degree of aromaticity have been lacking. Our method yields now a new tool to study and analyze electron currents at the resolution of one atom inside any nanostructure, in principle. The peer reviewers of our work considered this as a significant advancement in the field”, says Professor Häkkinen who coordinated the research.

This image illustrates the work,

Caption: The atomic structure of a gold nanoparticle protected by phosphine molecules (left) and magnetic-field-induced electron currents in a plane intersecting the center of the particle (right). The total electron current consists of two (paratropic and diatropic) components circulating in opposite directions. Credit: University of Jyväskylä/Omar Lopez Estrada

Here’s a link to and a citation for the paper,

Magnetically induced currents and aromaticity in ligand-stabilized Au and AuPt superatoms by Omar López-Estrada, Bernardo Zuniga-Gutierrez, Elli Selenius, Sami Malola & Hannu Häkkinen . Nature Communications volume 12, Article number: 2477 (2021) DOI: https://doi.org/10.1038/s41467-021-22715 Published: 30 April 2021

This paper is open access.

Gold nanoparticle tattoo changes medical diagnostics?

The tattoos are in fact implantable sensors. Here’s more from an April 6, 2021 news item on ScienceDaily,

The idea of implantable sensors that continuously transmit information on vital values and concentrations of substances or drugs in the body has fascinated physicians and scientists for a long time. Such sensors enable the constant monitoring of disease progression and therapeutic success. However, until now implantable sensors have not been suitable to remain in the body permanently but had to be replaced after a few days or weeks. On the one hand, there is the problem of implant rejection because the body recognizes the sensor as a foreign object. On the other hand, the sensor’s color which indicates concentration changes has been unstable so far and faded over time. Scientists at Johannes Gutenberg University Mainz (JGU) have developed a novel type of implantable sensor which can be operated in the body for several months. The sensor is based on color-stable gold nanoparticles that are modified with receptors for specific molecules. Embedded into an artificial polymeric tissue, the nanogold is implanted under the skin where it reports changes in drug concentrations by changing its color.

An April 6, 2021 Johannes Gutenberg Universitaet Mainz press release (also on EurekAlert), which originated the news item, provides more detail about the proposed tattoo/implantable sensors,

Implant reports information as an “invisible tattoo”

Professor Carsten Sönnichsen’s research group at JGU has been using gold nanoparticles as sensors to detect tiny amounts of proteins in microscopic flow cells for many years. Gold nanoparticles act as small antennas for light: They strongly absorb and scatter it and, therefore, appear colorful. They react to alterations in their surrounding by changing color. Sönnichsen’s team has exploited this concept for implanted medical sensing.

To prevent the tiny particles from swimming away or being degraded by immune cells, they are embedded in a porous hydrogel with a tissue-like consistency. Once implanted under the skin, small blood vessels and cells grow into the pores. The sensor is integrated in the tissue and is not rejected as a foreign body. “Our sensor is like an invisible tattoo, not much bigger than a penny and thinner than one millimeter,” said Professor Carsten Sönnichsen, head of the Nanobiotechnology Group at JGU. Since the gold nanoparticles are infrared, they are not visible to the eye. However, a special kind of measurement device can detect their color noninvasively through the skin.

In their study published in Nano Letters, the JGU researchers implanted their gold nanoparticle sensors under the skin of hairless rats. Color changes in these sensors were monitored following the administration of various doses of an antibiotic. The drug molecules are transported to the sensor via the bloodstream. By binding to specific receptors on the surface of the gold nanoparticles, they induce color change that is dependent on drug concentration. Thanks to the color-stable gold nanoparticles and the tissue-integrating hydrogel, the sensor was found to remain mechanically and optically stable over several months.

Huge potential of gold nanoparticles as long-lasting implantable medical sensors

“We are used to colored objects bleaching over time. Gold nanoparticles, however, do not bleach but keep their color permanently. As they can be easily coated with various different receptors, they are an ideal platform for implantable sensors,” explained Dr. Katharina Kaefer, first author of the study.

The novel concept is generalizable and has the potential to extend the lifetime of implantable sensors. In future, gold nanoparticle-based implantable sensors could be used to observe concentrations of different biomarkers or drugs in the body simultaneously. Such sensors could find application in drug development, medical research, or personalized medicine, such as the management of chronic diseases.

Interdisciplinary team work brought success

Sönnichsen had the idea of using gold nanoparticles as implanted sensors already in 2004 when he started his research in biophysical chemistry as a junior professor in Mainz. However, the project was not realized until ten years later in cooperation with Dr. Thies Schroeder and Dr. Katharina Kaefer, both scientists at JGU. Schroeder was experienced in biological research and laboratory animal science and had already completed several years of research work in the USA. Kaefer was looking for an exciting topic for her doctorate and was particularly interested in the complex and interdisciplinary nature of the project. Initial results led to a stipend awarded to Kaefer by the Max Planck Graduate Center (MPGC) as well as financial support from Stiftung Rheinland-Pfalz für Innovation. “Such a project requires many people with different scientific backgrounds. Step by step we were able to convince more and more people of our idea,” said Sönnichsen happily. Ultimately, it was interdisciplinary teamwork that resulted in the successful development of the first functional implanted sensor with gold nanoparticles.

The researchers have provided an image which illustrates several elements described in the press release,

Caption: Gold nanoparticles embedded in a porous hydrogel can be implanted under the skin and used as medical sensors. The sensor is like an invisible tattoo revealing concentration changes of substances in the blood by color change. Credit: ill./©: Nanobiotechnology Group, JGU Department of Chemistry

Here’s a link to and a citation for the paper,

Implantable Sensors Based on Gold Nanoparticles for Continuous Long-Term Concentration Monitoring in the Body by Katharina Kaefer, Katja Krüger, Felix Schlapp, Hüseyin Uzun, Sirin Celiksoy, Bastian Flietel, Axel Heimann, Thies Schroeder, Oliver Kempski, and Carsten Sönnichsen. Nano Lett. 2021, XXXX, XXX, XXX-XXX DOI: https://doi.org/10.1021/acs.nanolett.1c00887 Publication Date:March 30, 2021 © 2021 The Authors. Published by American Chemical Society

This paper is behind a paywall.

Put a ring on it: preventing clumps of gold nanoparticles

Caption: A comparison of how linear PEG (left) and cyclic PEG (right) attach to a gold nanoparticle Credit: Yubo Wang, Takuya Yamamoto

A January 20, 2021 news item on phys.org focuses on work designed to stop gold nanoparticles from clumping together (Note: A link has been removed),

Hokkaido University scientists have found a way to prevent gold nanoparticles from clumping, which could help towards their use as an anti-cancer therapy.

Attaching ring-shaped synthetic compounds to gold nanoparticles helps them retain their essential light-absorbing properties, Hokkaido University researchers report in the journal Nature Communications.

A January 20, 2021 Hokkaido University press release (also on EurekAlert but published Jan. 21, 2020), which originated the news item, elaborates on the work,

Metal nanoparticles have unique light-absorbing properties, making them interesting for a wide range of optical, electronic and biomedical applications. For example, if delivered to a tumour, they could react with applied light to kill cancerous tissue. A problem with this approach, though, is that they easily clump together in solution, losing their ability to absorb light. This clumping happens in response to a variety of factors, including temperature, salt concentration and acidity.

Scientists have been trying to find ways to ensure nanoparticles stay dispersed in their target environments. Covering them with polyethylene glycol, otherwise known as PEG, has been relatively successful at this in the case of gold nanoparticles. PEG is biocompatible and can prevent gold surfaces from clumping together in the laboratory and in living organisms, but improvements are still needed.

Applied chemist Takuya Yamamoto and colleagues at Hokkaido University, The University of Tokyo, and Tokyo Institute of Technology found that mixing gold nanoparticles with ring-shaped PEG, rather than the normally linear PEG, significantly improved dispersion. The ‘cyclic-PEG’ (c-PEG) attaches to the surfaces of the nanoparticles without forming chemical bonds with them, a process called physisorption. The coated nanoparticles remained dispersed when frozen, freeze-dried and heated.

The team tested the c-PEG-covered gold nanoparticles in mice and found that they cleared slowly from the blood and accumulated better in tumours compared to gold nanoparticles coated with linear PEG. However, accumulation was lower than desired levels, so the researchers recommend further investigations to fine-tune the nanoparticles for this purpose.

Associate Professor Takuya Yamamoto is part of the Laboratory of Chemistry of Molecular Assemblies at Hokkaido University, where he studies the properties and applications of various cyclic chemical compounds.

Here’s a link to and a citation for the paper,

Enhanced dispersion stability of gold nanoparticles by the physisorption of cyclic poly(ethylene glycol) by Yubo Wang, Jose Enrico Q. Quinsaat, Tomoko Ono, Masatoshi Maeki, Manabu Tokeshi, Takuya Isono, Kenji Tajima, Toshifumi Satoh, Shin-ichiro Sato, Yutaka Miura & Takuya Yamamoto. Nature Communications volume 11, Article number: 6089 (2020) DOI: https://doi.org/10.1038/s41467-020-19947-8 Published: 30 November 2020

This paper is open access.

Spotting the difference between dengue and Zika infections with gold nanosensors

This July 29, 2020 news item on Nanowerk features research from Brazil,

A new class of nanosensor developed in Brazil could more accurately identify dengue and Zika infections, a task that is complicated by their genetic similarities and which can result in misdiagnosis.

The technique uses gold nanoparticles and can “observe” viruses at the atomic level, according to a study published in Scientific Reports (“Nanosensors based on LSPR are able to serologically differentiate dengue from Zika infections”).

Belonging to the Flavivirus genus in the Flaviviridae family, Zika and dengue viruses share more than 50 per cent similarity in their amino acid sequence. Both viruses are spread by mosquitos and can have long-term side effects. The Flaviviridae virus family was named after the yellow fever virus and comes from the Latin word for golden, or yellow, in colour.

“Diagnosing [dengue virus] infections is a high priority in countries affected by annual epidemics of dengue fever. The correct diagnostic is essential for patient managing and prognostic as there are no specific antiviral drugs to treat the infection,” the authors say.

More than 1.8 million people are suspected to have been infected with dengue so far this year in the Americas, with 4000 severe cases and almost 700 deaths, the Pan American Health Organization says. The annual global average is estimated to be between 100 million and 400 million dengue infections, according to the World Health Organization.

Flávio Fonseca, study co-author and researcher at the Federal University of Minas Gerais, tells SciDev.Net it is almost impossible to differentiate between dengue and Zika viruses.

“A serologic test that detects antibodies against dengue also captures Zika-generated antibodies. We call it cross-reactivity,” he says.

Meghie Rodrigues’ July 29, 2020 article for SciDev.net, which originated the news item, delves further into the work,

Co-author and virologist, Maurício Nogueira, tells SciDev.Net that avoiding cross-reactivity is crucial because “dengue is a disease that kills — and can do so quickly if the right diagnosis is not made. As for Zika, it offers risks for foetuses to develop microcephaly, and we can’t let pregnant women spend seven or eight months wondering whether they have the virus or not.”

There is also no specific antiviral treatment for Zika and the search for a vaccine is ongoing.

Virus differentiation is important to accurately measure the real impact of both diseases on public health. The most widely used blood test, the enzyme-linked immunosorbent assay (ELISA), is limited in its ability to tell the difference between the viruses, the authors say.

As dengue has four variations, known as serotypes, the team created four different nanoparticles and covered each of them with a different dengue protein. They applied ELISA serum and a blood sample. The researchers found that sample antibodies bound with the viruses’ proteins, changing the pattern of electrons on the gold nanoparticle surface.

Should you check out Rodrigues’ entire article, you might want to take some time to explore SciDev.net to find science news from countries that don’t often get the coverage they should.

Here’s a link to and a citation for the researchers’ paper,

Nanosensors based on LSPR are able to serologically differentiate dengue from Zika infections by Alice F. Versiani, Estefânia M. N. Martins, Lidia M. Andrade, Laura Cox, Glauco C. Pereira, Edel F. Barbosa-Stancioli, Mauricio L. Nogueira, Luiz O. Ladeira & Flávio G. da Fonseca. Scientific Reports volume 10, Article number: 11302 (2020) DOI: https://doi.org/10.1038/s41598-020-68357-9 Published: 09 July 2020

This paper is open access.

Water-based gold rush

It seems water can play an important role when using nanocatalysts made of gold nanoparticles combined with metal oxides. From a July 27, 2020 news item on ScienceDaily,

Nanocatalysts made of gold nanoparticles dispersed on metal oxides are very promising for the industrial, selective oxidation of compounds, including alcohols, into valuable chemicals. They show high catalytic activity, particularly in aqueous solution. A team of researchers from Ruhr-Universität Bochum (RUB) has been able to explain why: Water molecules play an active role in facilitating the oxygen dissociation needed for the oxidation reaction. The team of Professor Dominik Marx, Chair of Theoretical Chemistry, reports in the high-impact journal ACS Catalysis on 14 July 2020.

A July 27, 2020 Ruhr-University Bochum (RUB) press release (also on EurekAlert), which originated the news item, offers more detail,

Rushing for gold

Most industrial oxidation processes involve the use of agents, such as chlorine or organic peroxides, that produce toxic or useless by-products. Instead, using molecular oxygen, O2, and splitting it to obtain the oxygen atoms needed to produce specific products would be a greener and more attractive solution. A promising medium for this approach is the gold/metal oxide (Au/TiO2) system, where the metal oxide titania (TiO2) supports nanoparticles of gold. These nanocatalysts can catalyse the selective oxidation of molecular hydrogen, carbon monoxide and especially alcohols, among others. A crucial step behind all reactions is the dissociation of O2, which comprises a usually high energy barrier. And a crucial unknown in the process is the role of water, since the reactions take place in aqueous solutions.

In a 2018 study, the RUB group of Dominik Marx, Chair of Theoretical Chemistry and Research Area coordinator in the Cluster of Excellence Ruhr Explores Solvation (Resolv), already hinted that water molecules actively participate in the oxidative reaction: They enable a stepwise charge-transfer process that leads to oxygen dissociation in the aqueous phase. Now, the same team reveals that solvation facilitates the activation of molecular oxygen (O2) at the gold/metal oxide (Au/TiO2) nanocatalyst: In fact, water molecules help to decrease the energy barrier for the O2 dissociation. The researchers quantified that the solvent curbs the energy costs by 25 per cent compared to the gas phase. “For the first time, it has been possible to gain insights into the quantitative impact of water on the critical O2 activation reaction for this nanocatalyst – and we also understood why,” says Dominik Marx.

Mind the water molecules

The RUB researchers applied computer simulations, the so-called ab initio molecular dynamics simulations, which explicitly included not only the catalyst but also as many as 80 surrounding water molecules. This was key to gain deep insights into the liquid-phase scenario, which contains water, in direct comparison to the gas phase conditions, where water is absent. “Previous computational work employed significant simplifications or approximations that didn’t account for the true complexity of such a difficult solvent, water,” adds Dr. Niklas Siemer who recently earned his PhD at RUB based on this research.

Scientists simulated the experimental conditions with high temperature and pressure to obtain the free energy profile of O2 in both liquid and gas phase. Finally, they could trace back the mechanistic reason for the solvation effect: Water molecules induce an increase of local electron charge towards oxygen that is anchored at the nanocatalyst perimeter; this in turn leads to the less energetic costs for the dissociation. In the end, say the researchers, it’s all about the unique properties of water: “We found that the polarizability of water and its ability to donate hydrogen bonds are behind oxygen activation,” says Dr. Munoz-Santiburcio. According to the authors, the new computational strategy will help to understand and improve direct oxidation catalysis in water and alcohols.

Here’s a link to and a citation for the paper,

Solvation-Enhanced Oxygen Activation at Gold/Titania Nanocatalysts by Niklas Siemer, Daniel Muñoz-Santiburcio, and Dominik Marx. ACS Catal. 2020, 10, 15, 8530–8534 DOI: https://doi.org/10.1021/acscatal.0c01326 Publication Date: July 14, 2020 Copyright © 2020 American Chemical Society

This paper is behind a paywall.

Gold nanoparticles make a new promise: a non-invasive COVID-19 breathalyser

I believe that swab they stick up your nose to test for COVDI-19 is 10 inches long so it seems to me that discomfort or unpleasant are not the words that best describe the testing experience .

Hopefully, no one will have to find inadequate vocabulary for this new COVID-19 testing assuming that future trials are successful and they are able to put the technology into production. From an August 19, 2020 news item on Nanowerk,

Few people who have undergone nasopharyngeal swabs for coronavirus testing would describe it as a pleasant experience. The procedure involves sticking a long swab up the nose to collect a sample from the back of the nose and throat, which is then analyzed for SARS-CoV-2 RNA [ribonucleic acid] by the reverse-transcription polymerase chain reaction (RT-PCR).

Now, researchers reporting in [American Chemical Society] ACS Nano (“Multiplexed Nanomaterial-Based Sensor Array for Detection of COVID-19 in Exhaled Breath”) have developed a prototype device that non-invasively detected COVID-19 in the exhaled breath of infected patients.

An August 19, 2020 ACS news release (also received via email and on EurekAlert), which originated the news item, provides more technical details,

In addition to being uncomfortable, the current gold standard for COVID-19 testing requires RT-PCR, a time-consuming laboratory procedure. Because of backlogs, obtaining a result can take several days. To reduce transmission and mortality rates, healthcare systems need quick, inexpensive and easy-to-use tests. Hossam Haick, Hu Liu, Yueyin Pan and colleagues wanted to develop a nanomaterial-based sensor that could detect COVID-19 in exhaled breath, similar to a breathalyzer test for alcohol intoxication. Previous studies have shown that viruses and the cells they infect emit volatile organic compounds (VOCs) that can be exhaled in the breath.

The researchers made an array of gold nanoparticles linked to molecules that are sensitive to various VOCs. When VOCs interact with the molecules on a nanoparticle, the electrical resistance changes. The researchers trained the sensor to detect COVID-19 by using machine learning to compare the pattern of electrical resistance signals obtained from the breath of 49 confirmed COVID-19 patients with those from 58 healthy controls and 33 non-COVID lung infection patients in Wuhan, China. Each study participant blew into the device for 2-3 seconds from a distance of 1¬-2 cm. Once machine learning identified a potential COVID-19 signature, the team tested the accuracy of the device on a subset of participants. In the test set, the device showed 76% accuracy in distinguishing COVID-19 cases from controls and 95% accuracy in discriminating COVID-19 cases from lung infections. The sensor could also distinguish, with 88% accuracy, between sick and recovered COVID-19 patients. Although the test needs to be validated in more patients, it could be useful for screening large populations to determine which individuals need further testing, the researchers say.

The authors acknowledge funding from the Technion-Israel Institute of Technology.

Here’s a link to and a citation for the paper,

Multiplexed Nanomaterial-Based Sensor Array for Detection of COVID-19 in Exhaled Breath by Benjie Shan, Yoav Y Broza, Wenjuan Li, Yong Wang, Sihan Wu, Zhengzheng Liu, Jiong Wang, Shuyu Gui, Lin Wang, Zhihong Zhang, Wei Liu, Shoubing Zhou, Wei Jin, Qianyu Zhang, Dandan Hu, Lin Lin, Qiujun Zhang, Wenyu Li, Jinquan Wang, Hu Liu, Yueyin Pan, and Hossam Haick. ACS Nano 2020, XXXX, XXX, XXX-XXX DOI: https://doi.org/10.1021/acsnano.0c05657 Publication Date:August 18, 2020 Copyright © 2020 American Chemical Society

This paper is behind a paywall.