Category Archives: health and safety

Nanotechnology-enabled pain relief for tooth sensitivity

A November 23, 2021 news item on phys.org announces research from Australia that may lead to pain relief for anyone with sensitive teeth,

In an Australian first, researchers from the University of Queensland have used nanotechnology to develop effective ways to manage tooth sensitivity.

Dr. Chun Xu from UQ’s [University of Queensland] School of Dentistry said the approach might provide more effective long-term pain relief for people with sensitive teeth, compared to current options.

A November 23, 2021 University of Queensland press release, which originated the news item, describes the condition leading to tooth sensitivity and how the proposed solution works (Note: Links have been removed),

“Dentin tubules are located in the dentin, one of the layers below the enamel surface of your teeth,” Dr Xu said.

“When tooth enamel has been worn down, and the dentin are exposed, eating or drinking something cold or hot can cause a sudden sharp flash of pain.

“The nanomaterials used in this preclinical study can rapidly block the exposed dentin tubules and prevent the unpleasant pain.

“Our approach acts faster and lasts longer than current treatment options.

“The materials could be developed into a paste, so people who have sensitive teeth could simply apply this paste to the tooth and massage for one to three minutes.

“The next step is clinical trials.”

Tooth sensitivity affects up to 74 per cent of the population, at times severely impacting quality of life and requiring expensive treatment.

“If clinical trials are successful people will benefit from this new method that can be used at home, without the need to go to a dentist in the near future,” Dr Xu said.

“We hope this study encourages more research using nanotechnology to address dental problems.”

The team also included researchers from UQ’s Australian Institute for Bioengineering and Nanotechnology (AIBN.

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

Calcium-Doped Silica Nanoparticles Mixed with Phosphate-Doped Silica Nanoparticles for Rapid and Stable Occlusion of Dentin Tubules by Yuxue Cao, Chun Xu, Patricia P. Wright, Jingyu Liu, Yueqi Kong, Yue Wang, Xiaodan Huang, Hao Song, Jianye Fu, Fang Gao, Yang Liu, Laurence J. Walsh, and Chang Lei. ACS Appl. Nano Mater. 2021, 4, 9, 8761–8769 DOI: https://doi.org/10.1021/acsanm.1c01365 Publication Date:August 25, 2021 Copyright © 2021 American Chemical Society

This paper is behind a paywall.

Nanoparticles for prolonged anti-lice protection

Caption Graphical abstract [the animal is a capybara, world’s largest rodent] Credit: Kazan Federal University, Louisiana Tech University, Gubkin University

A September 28, 2021Kazan Federal University (Russia) press release (also on EurekAlert; Source text: Larisa Busil Photo: Rawil Fakhrullin) announces news that could lead to relief for anyone who owns animals,

An international researcher team of Louisiana Tech University, Gubkin University [also known as, Gubkin Russian State University of Oil and Gas] and Kazan Federal University reported the fabrication of nanoscale insecticidal hair coating for prolonged anti-lice protection. The study was supported by the Russian Science Foundation.

“Treating agricultural and domestic animals infected with ectoparasites (such as lice, fleas, chewing lice, etc.) is among the primary challenges of veterinary medicine and agriculture. In case of mass infestation, regular measures, such as isolation of infected animals or repeated reapplication of insecticides, are not always effective. These methods are time-limited and provide a short-term therapeutic effect,” explains co-author Rawil Fakhrullin, Head of Kazan University’s Bionanotechnology Lab. “Using an inorganic nanoscale carrier as a component of a therapeutic formulation for topical application of insecticides might be the optimal way to address this challenge.”

Halloysite, a natural nanosized tubular mineral, was used as a drug carrier capable of forming a durable and uniform coating on the surface of animal hair.

“Loading an insecticidal drug, permethrin, into halloysite nanotubes reduces the release rate, leading to fewer re-treatments and fewer side effects,” continues Dr. Fakhrullin.

The paper shows that after goat hair samples were treated with halloysite-based nanocontainers, a stable 2-3 micron waterproof coating was formed on the surface of the hair, suitable for long-term antiparasitic protection.

“Long-term insecticidal activity is the result of the gradual release of the drug from the nanotubes. A formulation based on halloysite retains its protective antiparasitic properties after washing the animal’s hair with water. This stable and water-resistant composite coating provides a drug dose effective for long-term protection of animals,” says the interviewee.

The authors also examined the hair structure of the capybara, world’s largest rodent native to South America. They found that the wax-like layer present on the hair surface of this semi-aquatic animal facilitates the formation of a denser and more durable coating of halloysite than in terrestrial animals (guinea pigs and goats). The wax helps retaining nanoclay particles on the surface of the animal’s hair.

Dr. Fakhrullin comments about the test subjects, “We studied the suppressive effects of nanocontainers on goat ectoparasites Damalinia caprae from the Trichodectidae family. At the same time, our technique can be effective towards other types of lice, since these parasites live in hair and maintain close contact with hair cuticles, regardless of the animal’s dietary preferences. We believe that this approach can be used for long-term and sustainable antiparasitic protection of farm animals, especially if other insecticidal preparations are encapsulated in addition to permethrin. In addition, similar drugs can be used for the prevention or treatment of head lice in humans.”

Furthermore, the described material can also be helpful in treating fur in zoological collections.

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

Clay Nanotube Immobilization on Animal Hair for Sustained Anti-Lice Protection by Naureen Rahman, Faith Hannah Scott, Yuri Lvov, Anna Stavitskaya, Farida Akhatova, Svetlana Konnova, Gӧlnur Fakhrullina and Rawil Fakhrullin. Pharmaceutics 2021, 13(9), 1477; DOI: https://doi.org/10.3390/pharmaceutics13091477 Published: 15 September 2021

This paper is open access.

Methylene Blue-based sunscreen—anti-aging and coral reef safe

In any event, it’s time to start thinking about sunscreens (for those of us in the Northern Hemisphere.) One other thing, this is informational; it is not an endorsement. A March 1, 2022 Mblue Labs product announcement on EurekAlert (also on EIN Presswire) describes some of the research that went into this new sunscreen,

(Bethesda, MD – March 1, 2022) Mblue Labs releases the first sunscreen based on a recent study that found Methylene Blue, a century old medicine, to be  a highly effective, broad-spectrum UV irradiation protector that absorbs UVA and UVB, repairs ROS (Free Radicals) and UV irradiation induced DNA damages, and is safe for coral reefs. The research paper, “Ultraviolet radiation protection potentials of Methylene Blue for human skin and coral reef health ” was published in Nature’s Scientific Reports (5/28/2021) https://www.nature.com/articles/s41598-021-89970-2 [open access].

80% of today’s sunscreens use Oxybenzone as a chemical UV blocker, despite multiple studies that have shown it expedites the destruction of coral reefs. Several states and countries have now banned the use of Oxybenzone and its derivatives to stop the devastating effects on the world’s marine ecosystem. In addition, consumers focus primarily on the Sun Protection Factor (SPF) to prevent sunburns and potentially dangerous long-term health issues. However, SPF only measures UVB exposure, leaving sunscreen users vulnerable to UVA-triggered oxidative stress and photo-aging.

Our peer-reviewed study demonstrates that Methylene Blue is an effective UV blocker with a number of highly desired characteristics as a novel ingredient to be included in sunscreens. It shows a broad spectrum absorption of both UVA and UVB rays, promotes DNA damage repair, combats reactive oxygen species (ROS) induced by UVA, and most importantly, poses no harm to coral reefs.” says the study’s senior author Dr. Kan Cao, Founder of Mblue Labs, Bluelene Skincare and a Professor at the University of Maryland Department of Cell Biology and Molecular Genetics.

Mblue Labs and the University of Maryland have a pending patent on the property of Methylene Blue as an effective UV blocking agent that also delays skin aging and promotes DNA damage repair. The company’s first anti-aging sunscreen called “Bluevado SunFix”, contains the FDA approved, safe active ingredients Zinc Oxide and Titanium Dioxide, together with an optimized dosage of Methylene Blue. 

“Our Vision for this novel multifunctionsunscreen is deeply rooted in our concern for coral reefs – the rainforest of the ocean. We look forward to working with the industry and the FDA to get Methylene Blue included in the sunscreen monograph. We are confident that Bluevado SunFix not only delivers broad spectrum UVB/UVA protection and post sun repair, but also provides the full anti-aging benefits of our Bluelene Moisturizer with the same cosmetic elegance.”  says Jasmin EL Kordi, CEO Mblue Labs.

This research was supported by a National Science Foundation (NSF) Small Business Technology Transfer Grant (Grant: 1842745). This press release does not necessarily represent the views of the NSF. This study was conducted jointly by researchers at Mblue Labs and the University of Maryland.

About Mblue Labs + Bluelene

MBlue Labs provides revolutionary anti-aging technology to consumers around the world.  The company’s clinical skincare brand Bluelene uses patented ingredient Methylene Blue to repair and protect skin on the mitochondrial level. Mblue Labs’ recent research demonstrates Methylene Blue as the new retinol challenger for anti-aging treatments, in addition to its exciting properties as a new UV sunscreen.

I went looking for the new sunscreen (Bluevado SunFix) and found this,

$58.00

Bluevado SunFix is the first FDA-approved anti-aging sunscreen with Methylene Blue. Methylene Blue’s unique ability to promote skin cell health, repair/delay skin aging and protect against UVA and UVB radiation, is now captured in the bravado of this revolutionary SPF Day Cream.

Our innovative formulation blends Methylene Blue with proven minerals to outperform Oxybenzone, deliver cosmetic elegance, and protect our precious coral reefs from harmful substances. 

Methylene Blue is a preferred alternative to retinol for sensitive skin sufferers and with SunFix there is no retinol sun sensitivity.

Bluevado SunFix is proudly made in the USA and is formulated for ALL skin types.

Preorder now to reserve your SunFix. First shipments are available in mid-March [2022].

Application:

Use as a daily SPF Moisturizer. For sun protection apply 15mins before sun exposure and reapply after 40 minutes of swimming or sweating.

Benefits:

Broad-spectrum UVA/UVB sun protection 

Prevents pre-mature aging 

Repairs photo-aging DNA damage caused by UVA exposure

Reduces fine lines, crows feet, and wrinkles

Improves skin elasticity & firmness

Provides all-day skin hydration

Protects coral reefs

Free USPS shipping for all domestic orders over $34!

Ingredients:

Active Ingredients: Zinc Oxide 8.2%, Titanium Dioxide 2.8%   

Inactive Ingredients: Water (Aqua), Caprylic/Capric Triglyceride, C13-15 Alkane, Cetearyl Alcohol, Glycerin, Oryza Sativa (Rice) Bran Oil, Heptyl Undecylenate, Cetyl Alcohol, Argania Spinosa (Argan) Kernel Oil, Tocopheryl Acetate, Glyceryl Stearate, PEG-100 Stearate, Capryloyl Glycerin/Sebacic Acid Copolymer, Sorbitan Laurate, Butyrospermum Parkii (Shea) Butter, Cocos Nucifera (Coconut) Oil, Bisabolol, Xanthan Gum, Polyhydroxystearic Acid, Jojoba Esters, Polysorbate 60, Ascorbyl Palmitate, Citrus Aurantium Bergamia (Bergamot) Peel Oil, Pelargonium Graveolens (Geranium) Leaf Oil, Citrus Grandis (Grapefruit) Peel Oil, Lavandula Angustifolia (Lavender) Oil, Phenoxyethanol, Caprylyl Glycol, Methylene Blue. [emphasis mine]

Caution: For external use only. Keep out of reach of children. In case of irritation or allergic reaction, discontinue use and consult your physician.

There’s 3 fl oz or 90 mL of product in the tube and it’s SPF 21. (If memory serves, Methylene Blue’s placement at the end of the list ingredients means that it’s the ingredient that weighs the least.)

Again, I am not endorsing this product. That said, it does look interesting.

Caption: Corals exposed to Methylene Blue remain healthy. Credit: Mblue Labs

BTW, Finding a product announcement on EurekAlert (online science news service sponsored by the American Association for the Advancement of Science [AAAS]) was a little unexpected but only because I was ignorant of their Content Eligibility Guidelines (scroll down to Business Announcements). Duly noted.

Smart dental implant resists bacterial growth and generates own electricity

A “smart” dental implant could improve upon current devices by employing biofilm-resisting nanoparticles and a light powered by biomechanical forces to promote health of the surrounding gum tissue. (Image: Courtesy of Albert Kim)

A September 9, 2021 news item on ScienceDaily announces research into ‘smart’ dental implants,

More than 3 million people in America have dental implants, used to replace a tooth lost to decay, gum disease, or injury. Implants represent a leap of progress over dentures or bridges, fitting much more securely and designed to last 20 years or more.

But often implants fall short of that expectation, instead needing replacement in five to 10 years due to local inflammation or gum disease, necessitating a repeat of a costly and invasive procedure for patients.

“We wanted to address this issue, and so we came up with an innovative new implant,” says Geelsu Hwang, an assistant professor in the University of Pennsylvania School of Dental Medicine, who has a background in engineering that he brings to his research on oral health issues.

The novel implant would implement two key technologies, Hwang says. One is a nanoparticle-infused material that resists bacterial colonization. And the second is an embedded light source to conduct phototherapy, powered by the natural motions of the mouth, such as chewing or toothbrushing. In a paper in the journal ACS Applied Materials & Interfaces and a 2020 paper in the journal Advanced Healthcare Materials, Hwang and colleagues lay out their platform, which could one day be integrated not only into dental implants but other technologies, such as joint replacements, as well.

A September 9, 2021 University of Pennsylvania news release (also on EurekAlert), which originated the news item, provides more technical details about the proposed technology,

“Phototherapy can address a diverse set of health issues,” says Hwang. “But once a biomaterial is implanted, it’s not practical to replace or recharge a battery. We are using a piezoelectric material, which can generate electrical power from natural oral motions to supply a light that can conduct phototherapy, and we find that it can successfully protect gingival tissue from bacterial challenge.”

In the paper, the material the researchers explored was barium titanate (BTO), which has piezoelectric properties that are leveraged in applications such as capacitators and transistors, but has not yet been explored as a foundation for anti-infectious implantable biomaterials. To test its potential as the foundation for a dental implant, the team first used discs embedded with nanoparticles of BTO and exposed them to Streptococcus mutans, a primary component of the bacterial biofilm responsible for tooth decay commonly known as dental plaque. They found that the discs resisted biofilm formation in a dose-dependent manner. Discs with higher concentrations of BTO were better at preventing biofilms from binding.

While earlier studies had suggested that BTO might kill bacteria outright using reactive oxygen species generated by light-catalyzed or electric polarization reactions, Hwang and colleagues did not find this to be the case due to the short-lived efficacy and off-target effects of these approaches. Instead, the material generates enhanced negative surface charge that repels the negatively charged cell walls of bacteria. It’s likely that this repulsion effect would be long-lasting, the researchers say.

“We wanted an implant material that could resist bacterial growth for a long time because bacterial challenges are not a one-time threat,” Hwang says.

The power-generating property of the material was sustained and in tests over time the material did not leach. It also demonstrated a level of mechanical strength comparable to other materials used in dental applications.

Finally, the material did not harm normal gingival tissue in the researchers’ experiments, supporting the idea that this could be used without ill effect in the mouth.

The technology is a finalist in the Science Center’s research accelerator program, the QED Proof-of-Concept program. As one of 12 finalists, Hwang and colleagues will receive guidance from experts in commercialization. If the project advances to be one of three finalists, the group has the potential to receive up to $200,000 in funding.

In future work, the team hopes to continue to refine the “smart” dental implant system, testing new material types and perhaps even using assymetric properties on each side of the implant components, one that encourages tissue integration on the side facing the gums and one that resists bacterial formation on the side facing the rest of the mouth.

“We hope to further develop the implant system and eventually see it commercialized so it can be used in the dental field,” Hwang says.

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

Bimodal Nanocomposite Platform with Antibiofilm and Self-Powering Functionalities for Biomedical Applications by Atul Dhall, Sayemul Islam, Moonchul Park, Yu Zhang, Albert Kim, and Geelsu Hwang. ACS Appl. Mater. Interfaces 2021, 13, 34, 40379–40391 DOI: https://doi.org/10.1021/acsami.1c11791 Publication Date:August 18, 2021 Copyright © 2021 American Chemical Society

This paper is behind a paywall.

The work from 2020, mentioned in the news release, laid groundwork for the latest paper.

Human Oral Motion-Powered Smart Dental Implant (SDI) for In Situ Ambulatory Photo-biomodulation Therapy by Moonchul Park, Sayemul Islam, Hye-Eun Kim, Jonathan Korosto, Markus B. Blatz, Geelsu Hwang, and Albert Kim. Adv. Healthcare Mater. 2020, 9, 2000658 DOI: 10.1002/adhm.202000658 First published: 01 July 2020 © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimHuman

This paper is behind a paywall.

Nanomaterial shapes and forms affect passage through blood brain barrier (BBB)

I meant to get this published a lot sooner.

There seems to be a lot of excitement about this research. I got an embargoed press release further in advance than usual and now the embargo is lifted, it’s everywhere except, at the time of this writing (0920 PDT July 6, 2021), on the publisher’s (Proceedings of the National Academy of Sciences [PNAS]) website.

A July 5, 2021 news item on Medical Express announces the news,

Nanomaterials found in consumer and health-care products can pass from the bloodstream to the brain side of a blood-brain barrier model with varying ease depending on their shape—creating potential neurological impacts that could be both positive and negative, a new study reveals.

A July 5, 2021 University of Birmingham press release (also on EurekAlert), which originated the news item, delves into the details,

Scientists found that metal-based nanomaterials such as silver and zinc oxide can cross an in vitro model of the ‘blood brain barrier’ (BBB) as both particles and dissolved ions – adversely affecting the health of astrocyte cells, which control neurological responses.

But the researchers also believe that their discovery will help to design safer nanomaterials and could open up new ways of targeting hard-to-reach locations when treating brain disease.

Publishing its findings today in PNAS, an international team of researchers discovered that the physiochemical properties of metallic nanomaterials influence how effective they are at penetrating the in vitro model of the blood brain barrier and their potential levels of toxicity in the brain.

Higher concentration of certain shapes of silver nanomaterials and zinc oxide may impair cell growth and cause increased permeability of the BBB, which can lead to the BBB allowing easier brain access to these compounds.

The BBB plays a vital role in brain health by restricting the passage of various chemical substances and foreign molecules into the brain from surrounding blood vessels.

Impaired BBB integrity compromises the health of the central nervous system and increased permeability to foreign substances may eventually cause damage to the brain (neurotoxicity).

Study co-author Iseult Lynch, Professor of Environmental Nanosciences at the University of Birmingham, commented: “We found that silver and zinc oxide nanomaterials, which are widely used in various daily consumer and health-care products, passed through our in vitro BBB model, in the form of both particles and dissolved ions.

“Variation in shape, size and chemical composition can dramatically influence nanomaterials penetration through the (in vitro) blood brain barrier. This is of paramount importance for tailored medical application of nanomaterials – for example targeted delivery systems, bioimaging and assessing possible risks associated with each type of metallic nanomaterial.”

The BBB is a physical barrier composed of a tightly packed layer of endothelial cells surrounding the brain which separates the blood from the cerebrospinal fluid allowing the transfer of oxygen and essential nutrients but preventing the access of most molecules.

Recent studies found nanomaterials such as zinc oxide can accumulate on the brain side of the in vitro BBB in altered states which can affect neurological activity and brain health. Inhaled, ingested, and dermally-applied nanomaterials can reach the blood stream and a small fraction of these may cross the BBB – impacting on the central nervous system.

The researchers synthesised a library of metallic nanomaterials with different particle compositions, sizes, and shapes – evaluating their ability to penetrate the BBB using an in vitro BBB model, followed by assessment of their behaviour and fate in and beyond the model BBB.

Co-author Zhiling Guo, a Research Fellow at the University of Birmingham, commented: “”Understanding these materials’ behaviour once past the blood brain barrier is vital for evaluating the neurological effects arising from their unintentional entry into the brain. Neurotoxicity potential is greater in some materials than others, due to the different ways their shapes allow them to move and be transported.”

The research team tested varied sizes of cerium oxide and iron oxide, along with zinc oxide and four different shapes of silver – spherical (Ag NS), disc-like (Ag ND), rod-shaped (Ag NR) and nanowires (Ag NW).

Zinc oxide slipped through the in vitro BBB with the greatest ease. The researchers found spherical and disc-like silver nanomaterials underwent different dissolution regimes – gradually transforming to silver-sulfur compounds within the BBB, creating ‘easier’ entry pathways.

Zinc oxide is used as a bulking agent and a colorant. In over-the-counter drug products, it is used as a skin protectant and a sunscreen – reflecting and scattering UV radiation to help reduce or prevent sunburn and premature aging of the skin. Silver is used in cosmetic and skincare products such as anti-aging creams.

There’s still a long way to go with this research. For anyone who’s unfamiliar with the term ‘in vitro’, the rough translation is ‘in glass’ meaning test tubes, petri dishes, etc. are used. Even though the research paper has been peer-reviewed (not a perfect process), once it becomes available there will be added scrutiny from scientists with regard to how the research was conducted and whether or not the conclusions drawn are reasonable. One more question should also be asked, are the results reproducible by other scientists?

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

Biotransformation modulates the penetration of metallic nanomaterials across an artificial blood–brain barrier model by Zhiling Guo, Peng Zhang, Swaroop Chakraborty, Andrew J Chetwynd, Fazel Abdolahpur Monikh, Christopher Stark, Hanene Ali-Boucetta, Sandra Wilson, Iseult Lynch, and Eugenia Valsami-Jones. PNAS 118 (28) e2105245118 DOI: https://doi.org/10.1073/pnas.2105245118 Published: July 13, 2021

This paper appears to be open access.

Use AI to reduce worries about nanoparticles in food

A June 16, 2021 news item on ScienceDaily announces research into the impact that engineered metallic nanoparticles used in agricultural practices have on food,

While crop yield has achieved a substantial boost from nanotechnology in recent years, alarms over the health risks posed by nanoparticles within fresh produce and grains have also increased. In particular, nanoparticles entering the soil through irrigation, fertilizers and other sources have raised concerns about whether plants absorb these minute particles enough to cause toxicity.

In a new study published online in the journal Environmental Science and Technology, researchers at Texas A&M University have used machine learning [a form of artificial intelligence {AI}] to evaluate the salient properties of metallic nanoparticles that make them more susceptible for plant uptake. The researchers said their algorithm could indicate how much plants accumulate nanoparticles in their roots and shoots.

A June 16, 2021 Texas A&M University news release (also on EurekAlert), which originated the news item, describes the research, which employed two different machine learning algorithms, in more detail,

Nanoparticles are a burgeoning trend in several fields, including medicine, consumer products and agriculture. Depending on the type of nanoparticle, some have favorable surface properties, charge and magnetism, among other features. These qualities make them ideal for a number of applications. For example, in agriculture, nanoparticles may be used as antimicrobials to protect plants from pathogens. Alternatively, they can be used to bind to fertilizers or insecticides and then programmed for slow release to increase plant absorption.

These agricultural practices and others, like irrigation, can cause nanoparticles to accumulate in the soil. However, with the different types of nanoparticles that could exist in the ground and a staggeringly large number of terrestrial plant species, including food crops, it is not clearly known if certain properties of nanoparticles make them more likely to be absorbed by some plant species than others.

“As you can imagine, if we have to test the presence of each nanoparticle for every plant species, it is a huge number of experiments, which is very time-consuming and expensive,” said Xingmao “Samuel” Ma, associate professor in the Zachry Department of Civil and Environmental Engineering. “To give you an idea, silver nanoparticles alone can have hundreds of different sizes, shapes and surface coatings, and so, experimentally testing each one, even for a single plant species, is impractical.”

Instead, for their study, the researchers chose two different machine learning algorithms, an artificial neural network and gene-expression programming. They first trained these algorithms on a database created from past research on different metallic nanoparticles and the specific plants in which they accumulated. In particular, their database contained the size, shape and other characteristics of different nanoparticles, along with information on how much of these particles were absorbed from soil or nutrient-enriched water into the plant body.

Once trained, their machine learning algorithms could correctly predict the likelihood of a given metallic nanoparticle to accumulate in a plant species. Also, their algorithms revealed that when plants are in a nutrient-enriched or hydroponic solution, the chemical makeup of the metallic nanoparticle determines the propensity of accumulation in the roots and shoots. But if plants are grown in soil, the contents of organic matter and the clay in soil are key to nanoparticle uptake.

Ma said that while the machine learning algorithms could make predictions for most food crops and terrestrial plants, they might not yet be ready for aquatic plants. He also noted that the next step in his research would be to investigate if the machine learning algorithms could predict nanoparticle uptake from leaves rather than through the roots.

“It is quite understandable that people are concerned about the presence of nanoparticles in their fruits, vegetables and grains,” said Ma. “But instead of not using nanotechnology altogether, we would like farmers to reap the many benefits provided by this technology but avoid the potential food safety concerns.”

This image accompanies the paper’s research abstract,

[downloaded frm https://pubs.acs.org/doi/full/10.1021/acs.est.1c01603]

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

Prediction of Plant Uptake and Translocation of Engineered Metallic Nanoparticles by Machine Learning by Xiaoxuan Wang, Liwei Liu, Weilan Zhang, and Xingmao Ma. Environ. Sci. Technol. 2021, 55, 11, 7491–7500 DOI: https://doi.org/10.1021/acs.est.1c01603 Publication Date:May 17, 2021 Copyright © 2021 American Chemical Society

This paper is behind a paywall.

Autonopia will pilot automated window cleaning in Vancouver (Canada) in 2022

Construction worker working outdoors with the project. Courtesy: Autonopia

Kenneth Chan in a June 10, 2021 article for the Daily Hive describes a startup company in Vancouver (Canada), which hopes to run a pilot project in 2022 for its “HŌMĀN, a highly capable, fast and efficient autonomous machine, designed specifically for cleaning the glasses [windows] perfectly and quickly.” (The description is from Autonopia’s homepage.)

Chan’s June 10, 2021 article describe the new automated window washer as a roomba-like robot,

The business of washing windows on a tower with human labour is a dangerous, inefficient, and costly practice, but a Vancouver innovator’s robotic solution could potentially disrupt this service globally.

Researchers with robotic systems startup Autonopia have come up with a robot that can mimic the behaviour of human window washers, including getting into the nooks and crannies of all types of complicated building facades — any surface structure.

It is also far more efficient than humans, cleaning windows three to four times faster, and can withstand wind and cold temperatures. According to a [news?] release, the robot is described as a modular device with a plug-and-play design [emphasis mine] that allows it to work on any building without requiring any additional infrastructure to be installed.

While artificial intelligence and the robotic device replaces manual work, it still requires a skilled operator to oversee the cleaning.

“It’s intimidating, hard work that most workers don’t want to do, [emphasis mine]” said Autonopia co-founder Mohammad Dabiri, who came up with the idea after witnessing an accident in Southeast Asia [emphasis mine].

“There’s high overhead to manage the hiring, allocation and training of workers, and sometimes they quit as soon as it comes time to go on a high rise.”

“We realized this problem has existed for a while, and yet none of the available solutions has managed to scale,” said Kamali Hossein, the co-founder and CTO of Autonopia, and a Mitacs postdoctoral research [sic] in mechatronic systems engineering at Simon Fraser University.

To clarify, the company is Autonopia and the product the company is promoting is HŌMĀN, an automated or robotic window washer for tall buildings (towers).

HŌMĀN (as it’s written in the Encyclopedia Iranica) or Houmān, as it’s written in Wikipedia, seems to be a literary hero or, perhaps, superhero,

… is one of the most famous Turanian heroes in Shahnameh, the national epic of Greater Iran. Houmān is famous for his bravery, loyalty, and chivalry, such that even Iranians who are longtime enemies of Turanians admire his personality. He is a descendant of Tur, a son of Viseh and brother of Piran. Houmān is the highest ranking Turanian commander and after Piran, he is the second leading member of Viseh clan. Houman first appears in the story of Rostam and Sohrab, …

Autonopia’s website is very attractive and weirdly uninformative. I looked for a more in depth description of ‘plug and play’ and found this,

Modular and Maintainable

The design of simple, but highly capable and modular components, along with the overall simplicity of the robot structure allows for a shorter build time and maintenance turnover. …

Cleans any tower

The flexible and capable design of the robot allows it to adjust to the complexities of the structures and it can maneuver uneven surfaces of different buildings very quickly and safely. No tower is off-limits for HŌMĀN. It is designed to cater to the specific requirements of each high-rise

I wish there were more details about the hardware and the software, e.g., there’s no mention of artificial intelligence as mentioned in Chan’s article.

As for whether or not this is “intimidating, hard work that most workers don’t want to do,” I wonder how Mohammad Dabiri can be so certain. If this product is successful, it will have an impact on people who rely on this work for their livelihoods. Possibly adding some insult to injury, Dabiri and Hossein claim their product is better at the job than humans are.

Nobody can argue about making work safer but it would be nice if some of these eager, entrepreneurial types put some thought into the impact both positive and negative that their bright ideas can have on other people.

As for whether HŌMĀN can work on any tower, photographs like the one at the beginning of this posting, feature modern office buildings which look like glass sheets held together with steel and concrete. So, it doesn’t look likely to work (and it’s probably not feasible from a business perspective) on older buildings with fewer stories, stone ornamentation, and even more nooks and crannies. As for some of the newer buildings which feature odd shapes and are reintroducing ornamentation, I’d imagine that will be problematic. But perhaps the market is overseas where tall buildings can range from 65 stories to over 100 stories (Wikipedia ‘List of tallest buildings‘). After all the genesis for this project was an incident in Southeast Asia. Vancouver doesn’t have 65 story buildings—yet. But, I’m sure there’s a developer or two out there with some plans.

A library of properties for nanomaterials

Researchers at the University of Birmingham (UK) announced the development of a library of nanomaterial properties according to a June 8, 2021 news item on Nanowerk (Note: Links have been removed),

Researchers have developed a ‘library of properties’ to help identify the environmental impact of nanomaterials faster and more cost effectively.

Whilst nanomaterials have benefited a wide range of industries and revolutionized everyday life, there are concerns over potential adverse effects—including toxic effects following accumulation in different organs and indirect effects from transport of co-pollutants.

The European Union H2020-funded NanoSolveIT project is developing a ground-breaking computer-based Integrated Approach to Testing and Assessment (IATA) for the environmental health and safety of nanomaterials.

A June 8, 2021 University of Birmingham press release (also on EurekAlert) spells out the details,

Over the last two years, researchers from the University of Birmingham have worked with experts at NovaMechanics, in Nicosia, Cyprus to develop a decision support system in the form of both stand-alone open software and a Cloud platform.

The team has developed a freely available cloud library containing full physicochemical characterisation of 69 nanomaterials, plus calculated molecular descriptors to increase the value of the available information, details of which are published in NanoImpact. [link and citation follow]

Professor Iseult Lynch, from the University of Birmingham commented: “One of the limitations to widespread application of computer-based approaches is the lack of large well-organised high-quality datasets, or of data with adequate metadata that will allow dataset interoperability and their combination to create larger datasets.”

“Making the library of calculated and experimental descriptors available to the community, along with the detailed description of how they were calculated is a key first step towards filling this datagap.”

Development of the cloud-based nanomaterials library is the fifth freely available web-based application that the project has delivered.

Antreas Afantitis, from NovaMechanics, commented: “Over the last two years, this project has already presented some very impressive results with more than 30 publications, making NanoSolveIT one of the most active projects in the nanomaterials safety and informatics space.”

Concerns about nanomaterials are also arising as risk assessment is lagging behind product development, mainly because current approaches to assessing exposure, hazard and risk are expensive and time-consuming, and frequently involve testing in animal models. The NanoSolveIT project aspires to address these challenges.

The latest development aims to enrich our knowledge of nanomaterials properties and the link from property to (cytotoxic) effect. The enriched dataset contains over 70 descriptors per nanomaterial.

The dataset was used to develop a computer-based workflow to predict nanomaterials’ effective surface charge (zeta-potential) based on a set of descriptors that can be used to help design and produce safer and more functional nanomaterials.

The resulting predictive read-across model has been made publicly and freely available as a web service through the Horizon 2020 (H2020) NanoCommons project (http://enaloscloud.novamechanics.com/nanocommons/mszeta/ ) and via the H2020 NanoSolveIT Cloud Platform (https://mszeta.cloud.nanosolveit.eu/ ) to ensure accessibility to the community and interested stakeholders.

In addition, the full data set, ready for further computational modeling, is available through the NanoPharos database, as the project consortium supports the FAIR data principles – committing to making its data Findable, Accessible, Interoperable and Re-usable.

I quite like this image of how the scales are illustrated (BTW, you can find NanoSolveIT here the NanoCommons project [closing date May 15, 2021] here, and NovaMechanics here)

Scales of descriptors – from whole nanoparticle to unit cell to individual atoms Courtesy University of Birmingham and NanoSolveIT

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

Computational enrichment of physicochemical data for the development of a ζ-potential read-across predictive model with Isalos Analytics Platform by Anastasios G. Papadiamantis, Antreas Afantitis, Andreas Tsoumanis, Eugenia Valsami-Jones, Iseult Lynch, Georgia Melagraki. NanoImpact Volume 22, April 2021, 100308 DOI: https://doi.org/10.1016/j.impact.2021.100308 Available online 18 March 2021

This paper is open access.

Concrete collapse and research into durability

I have two items about concrete buildings, one concerns the June 24, 2021 collapse of a 12-storey condominium building in Surfside, close to Miami Beach in Florida. There are at least 20 people dead and, I believe, over 120 are still unaccounted for (July 2, 2021 Associated Press news item on Canadian Broadcasting Corporation news online website).

Miami collapse

Nate Berg’s June 25, 2021 article for Fast Company provides an instructive overview of the building collapse (Note: A link has been removed),

Why the building collapsed is not yet known [emphasis mine]. David Darwin is a professor of civil engineering at the University of Kansas and an expert in reinforced concrete structures, and he says the eventual investigation of the Surfside collapse will explore all the potential causes, ranging from movement in the foundation before the collapse, corrosion in the debris, and excessive cracking in the part of the building that remains standing. “There are all sorts of potential causes of failure,” Darwin says. “At this point, speculation is not helpful for anybody.”

Sometimes I can access the entire article, and at other times, only a few paragraphs; I hope you get access to all of it as it provides a lot of information.

The Surfside news puts this research from Northwestern University (Chicago, Illinois) into much sharper relief than might otherwise be the case. (Further on I have some information about the difference between cement and concrete and how cement leads to concrete.)

Smart cement for more durable roads and cities

Coincidentally, just days before the Miami Beach building collapse, a June 21, 2021 Northwestern University news release (also on EurekAlert), announced research into improving water and fracture resistance in cement,

Forces of nature have been outsmarting the materials we use to build our infrastructure since we started producing them. Ice and snow turn major roads into rubble every year; foundations of houses crack and crumble, in spite of sturdy construction. In addition to the tons of waste produced by broken bits of concrete, each lane-mile of road costs the U.S. approximately $24,000 per year to keep it in good repair.

Engineers tackling this issue with smart materials typically enhance the function of materials by increasing the amount of carbon, but doing so makes materials lose some mechanical performance. By introducing nanoparticles into ordinary cement, Northwestern University researchers have formed a smarter, more durable and highly functional cement.

The research was published today (June 21 [2021]) in the journal Philosophical Transactions of the Royal Society A.

With cement being the most widely consumed material globally and the cement industry accounting for 8% of human-caused greenhouse gas emissions, civil and environmental engineering professor Ange-Therese Akono turned to nanoreinforced cement to look for a solution. Akono, the lead author on the study and an assistant professor in the McCormick School of Engineering, said nanomaterials reduce the carbon footprint of cement composites, but until now, little was known about its impact on fracture behavior.

“The role of nanoparticles in this application has not been understood before now, so this is a major breakthrough,” Akono said. “As a fracture mechanics expert by training, I wanted to understand how to change cement production to enhance the fracture response.”

Traditional fracture testing, in which a series of light beams is cast onto a large block of material, involves lots of time and materials and seldom leads to the discovery of new materials.

By using an innovative method called scratch testing, Akono’s lab efficiently formed predictions on the material’s properties in a fraction of the time. The method tests fracture response by applying a conical probe with increasing vertical force against the surface of microscopic bits of cement. Akono, who developed the novel method during her Ph.D. work, said it requires less material and accelerates the discovery of new ones.

“I was able to look at many different materials at the same time,” Akono said. “My method is applied directly at the micrometer and nanometer scales, which saves a considerable amount of time. And then based on this, we can understand how materials behave, how they crack and ultimately predict their resistance to fracture.”

Predictions formed through scratch tests also allow engineers to make changes to materials that enhance their performance at the larger scale. In the paper, graphene nanoplatelets, a material rapidly gaining popularity in forming smart materials, were used to improve the resistance to fracture of ordinary cement. Incorporating a small amount of the nanomaterial also was shown to improve water transport properties including pore structure and water penetration resistance, with reported relative decreases of 76% and 78%, respectively.

Implications of the study span many fields, including building construction, road maintenance, sensor and generator optimization and structural health monitoring.

By 2050, the United Nations predicts two-thirds of the world population will be concentrated in cities. Given the trend toward urbanization, cement production is expected to skyrocket.

Introducing green concrete that employs lighter, higher-performing cement will reduce its overall carbon footprint by extending maintenance schedules and reducing waste.

Alternately, smart materials allow cities to meet the needs of growing populations in terms of connectivity, energy and multifunctionality. Carbon-based nanomaterials including graphene nanoplatelets are already being considered in the design of smart cement-based sensors for structural health monitoring.

Akono said she’s excited for both follow-ups to the paper in her own lab and the ways her research will influence others. She’s already working on proposals that look into using construction waste to form new concrete and is considering “taking the paper further” by increasing the fraction of nanomaterial that cement contains.

“I want to look at other properties like understanding the long-term performance,” Akono said. “For instance, if you have a building made of carbon-based nanomaterials, how can you predict the resistance in 10, 20 even 40 years?”

The study, “Fracture toughness of one- and two-dimensional nanoreinforced cement via scratch testing,” was supported by the National Science Foundation Division of Civil, Mechanical and Manufacturing Innovation (award number 18929101).

Akono will give a talk on the paper at The Royal Society’s October [2021] meeting, “A Cracking Approach to Inventing Tough New Materials: Fracture Stranger Than Friction,” which will highlight major advances in fracture mechanics from the past century.

I don’t often include these kinds of photos (one or more of the researchers posing (sometimes holding something) for the camera but I love the professor’s first name, Ange-Therese (which means angel in French, I don’t know if she ever uses the French spelling for Thérèse),

Caption: Professor Ange-Therese Akono holds a sample of her smart cement. Credit: Northwestern University

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

Fracture toughness of one- and two-dimensional nanoreinforced cement via scratch testing by Ange-Therese Akono. Philosophical Transactions of the Royal Society A: Mathematical, Physical & Engineering Sciences 2021 379 (2203): 20200288 DOI: 10.1098/rsta.2020.0288 Published June 21, 2021

This paper appears to be open access.

Cement vs. concrete

Andrew Logan’s April 3, 2020 article for MIT (Massachusetts Institute of Technology) News is a very readable explanation of how cement and concrete differ and how they are related,

There’s a lot the average person doesn’t know about concrete. For example, it’s porous; it’s the world’s most-used material after water; and, perhaps most fundamentally, it’s not cement.

Though many use “cement” and “concrete” interchangeably, they actually refer to two different — but related — materials: Concrete is a composite made from several materials, one of which is cement. [emphasis mine]

Cement production begins with limestone, a sedimentary rock. Once quarried, it is mixed with a silica source, such as industrial byproducts slag or fly ash, and gets fired in a kiln at 2,700 degrees Fahrenheit. What comes out of the kiln is called clinker. Cement plants grind clinker down to an extremely fine powder and mix in a few additives. The final result is cement.

“Cement is then brought to sites where it is mixed with water, where it becomes cement paste,” explains Professor Franz-Josef Ulm, faculty director of the MIT Concrete Sustainability Hub (CSHub). “If you add sand to that paste it becomes mortar. And if you add to the mortar large aggregates — stones of a diameter of up to an inch — it becomes concrete.”

Final thoughts

I offer my sympathies to the folks affected by the building collapse and my hopes that research will lead the way to more durable cement and, ultimately, concrete buildings.