Tag Archives: nanosensors

Spinning gold out of nanocellulose

If you’re hoping for a Rumpelstiltskin reference (there is more about the fairy tale at the end of this posting) and despite the press release’s headline, you won’t find it in this August 10, 2020 news item on Nanowerk,

When nanocellulose is combined with various types of metal nanoparticles, materials are formed with many new and exciting properties. They may be antibacterial, change colour under pressure, or convert light to heat.

“To put it simply, we make gold from nanocellulose”, says Daniel Aili, associate professor in the Division of Biophysics and Bioengineering at the Department of Physics, Chemistry and Biology at Linköping University.

The research group, led by Daniel Aili, has used a biosynthetic nanocellulose produced by bacteria and originally developed for wound care. The scientists have subsequently decorated the cellulose with metal nanoparticles, principally silver and gold. The particles, no larger than a few billionths of a metre, are first tailored to give them the properties desired, and then combined with the nanocellulose.

An August 10, 2020 Linköping University press release (also on EurekAlert), which originated the news item,expands on a few details about the work (sob … without mentioning Rumpelstiltskin),

“Nanocellulose consists of thin threads of cellulose, with a diameter approximately one thousandth of the diameter of a human hair. The threads act as a three-dimensional scaffold for the metal particles. When the particles attach themselves to the cellulose, a material that consists of a network of particles and cellulose forms”, Daniel Aili explains.

The researchers can determine with high precision how many particles will attach, and their identities. They can also mix particles of different metals and with different shapes – spherical, elliptical and triangular.

In the first part of a scientific article published in Advanced Functional Materials, the group describes the process and explains why it works as it does. The second part focusses on several areas of application.

One exciting phenomenon is the way in which the properties of the material change when pressure is applied. Optical phenomena arise when the particles approach each other and interact, and the material changes colour. As the pressure increases, the material eventually appears to be gold.

“We saw that the material changed colour when we picked it up in tweezers, and at first we couldn’t understand why”, says Daniel Aili.

The scientists have named the phenomenon “the mechanoplasmonic effect”, and it has turned out to be very useful. A closely related application is in sensors, since it is possible to read the sensor with the naked eye. An example: If a protein sticks to the material, it no longer changes colour when placed under pressure. If the protein is a marker for a particular disease, the failure to change colour can be used in diagnosis. If the material changes colour, the marker protein is not present.

Another interesting phenomenon is displayed by a variant of the material that absorbs light from a much broader spectrum visible light and generates heat. This property can be used for both energy-based applications and in medicine.

“Our method makes it possible to manufacture composites of nanocellulose and metal nanoparticles that are soft and biocompatible materials for optical, catalytic, electrical and biomedical applications. Since the material is self-assembling, we can produce complex materials with completely new well-defined properties,” Daniel Aili concludes.

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

Self‐Assembly of Mechanoplasmonic Bacterial Cellulose–Metal Nanoparticle Composites by Olof Eskilson, Stefan B. Lindström, Borja Sepulveda, Mohammad M. Shahjamali, Pau Güell‐Grau, Petter Sivlér, Mårten Skog, Christopher Aronsson, Emma M. Björk, Niklas Nyberg, Hazem Khalaf, Torbjörn Bengtsson, Jeemol James, Marica B. Ericson, Erik Martinsson, Robert Selegård, Daniel Aili. Advanced Functional Materials DOI: https://doi.org/10.1002/adfm.202004766 First published: 09 August 2020

This paper is open access.

As for Rumpelstiltskin, there’s this abut the story’s origins and its cross-cultural occurrence, from its Wikipedia entry,

“Rumpelstiltskin” (/ˌrʌmpəlˈstɪltskɪn/ RUMP-əl-STILT-skin[1]) is a fairy tale popularly associated with Germany (where it is known as Rumpelstilzchen). The tale was one collected by the Brothers Grimm in the 1812 edition of Children’s and Household Tales. According to researchers at Durham University and the NOVA University Lisbon, the story originated around 4,000 years ago.[2][3] However, many biases led some to take the results of this study with caution.[4]

The same story pattern appears in numerous other cultures: Tom Tit Tot in England (from English Fairy Tales, 1890, by Joseph Jacobs); The Lazy Beauty and her Aunts in Ireland (from The Fireside Stories of Ireland, 1870 by Patrick Kennedy); Whuppity Stoorie in Scotland (from Robert Chambers’s Popular Rhymes of Scotland, 1826); Gilitrutt in Iceland; جعيدان (Joaidane “He who talks too much”) in Arabic; Хламушка (Khlamushka “Junker”) in Russia; Rumplcimprcampr, Rampelník or Martin Zvonek in the Czech Republic; Martinko Klingáč in Slovakia; “Cvilidreta” in Croatia; Ruidoquedito (“Little noise”) in South America; Pancimanci in Hungary (from A Csodafurulya, 1955, by Emil Kolozsvári Grandpierre, based on the 19th century folktale collection by László Arany); Daiku to Oniroku (大工と鬼六 “A carpenter and the ogre”) in Japan and Myrmidon in France.

An earlier literary variant in French was penned by Mme. L’Héritier, titled Ricdin-Ricdon.[5] A version of it exists in the compilation Le Cabinet des Fées, Vol. XII. pp. 125-131.

The Cornish tale of Duffy and the Devil plays out an essentially similar plot featuring a “devil” named Terry-top.

All these tales are Aarne–Thompson type 500, “The Name of the Helper”.[6]

Should you be curious about the story as told by the Brothers Grimm, here’s the beginning to get you started (from the grimmstories.com Rumpelstiltskin webpage),

There was once a miller who was poor, but he had one beautiful daughter. It happened one day that he came to speak with the king, and, to give himself consequence, he told him that he had a daughter who could spin gold out of straw. The king said to the miller: “That is an art that pleases me well; if thy daughter is as clever as you say, bring her to my castle to-morrow, that I may put her to the proof.”

When the girl was brought to him, he led her into a room that was quite full of straw, and gave her a wheel and spindle, and said: “Now set to work, and if by the early morning thou hast not spun this straw to gold thou shalt die.” And he shut the door himself, and left her there alone. And so the poor miller’s daughter was left there sitting, and could not think what to do for her life: she had no notion how to set to work to spin gold from straw, and her distress grew so great that she began to weep. Then all at once the door opened, and in came a little man, who said: “Good evening, miller’s daughter; why are you crying?”

Enjoy! BTW, should you care to, you can find three other postings here tagged with ‘Rumpelstiltskin’. I think turning dross into gold is a popular theme in applied science.

Herbicide nanometric sensor could help diagnose multiple sclerosis

This research into nanometric sensors and multiple sclerosis comes from Brazil. According to a June 23, 2015 news item on Nanowerk (Note: A link has been removed),

The early diagnosis of certain types of cancer, as well as nervous system diseases such as multiple sclerosis and neuromyelitis optica, may soon be facilitated by the use of a nanosensor capable of identifying biomarkers of these pathological conditions (“A Nanobiosensor Based on 4-Hydroxyphenylpyruvate Dioxygenase Enzyme for Mesotrione Detection”).

The nanobiosensor was developed at the Federal University of São Carlos (UFSCar), Sorocaba, in partnership with the São Paulo Federal Institute of Education, Science & Technology (IFSP), Itapetininga, São Paulo State, Brazil. It was originally designed to detect herbicides, heavy metals and other pollutants.

A June 23, 2015 Fundação de Amparo à Pesquisa do Estado de São Paulo news release on EurekAlert, which originated the news item, describes the sensor as it was originally used and explains its new function as a diagnostic tool for multiple sclerosis and other diseases,

“It’s a highly sensitive device, which we developed in collaboration with Alberto Luís Dario Moreau, a professor at IFSP. “We were able to increase sensitivity dramatically by going down to the nanometric scale,” said physicist Fábio de Lima Leite, a professor at UFSCar and the coordinator of the research group.

The nanobiosensor consists of a silicon nitride (Si3N4) or silicon (Si) nanoprobe with a molecular-scale elastic constant and a nanotip coupled to an enzyme, protein or other molecule.

When this molecule touches a target of interest, such as an antibody or antigen, the probe bends as the two molecules adhere. The deflection is detected and measured by the device, enabling scientists to identify the target.

“We started by detecting herbicides and heavy metals. Now we’re testing the device for use in detecting target molecules typical of nervous system diseases, in partnership with colleagues at leading centers of research on demyelinating diseases of the central nervous system”

The migration from herbicide detection to antibody detection was motivated mainly by the difficulty of diagnosing demyelinating diseases, cancer and other chronic diseases before they have advanced beyond an initial stage.

The criteria for establishing a diagnosis of multiple sclerosis or neuromyelitis optica are clinical (supplemented by MRI scans), and patients do not always present with a characteristic clinical picture. More precise diagnosis entails ruling out several other diseases.

The development of nanodevices will be of assistance in identifying these diseases and reducing the chances of false diagnosis.

The procedure can be as simple as placing a drop of the patient’s cerebrospinal fluid on a glass slide and observing its interaction with the nanobiosensor.

“If the interaction is low, we’ll be able to rule out multiple sclerosis with great confidence,” Leite said. “High interaction will indicate that the person is very likely to have the disease.” In this case, further testing would be required to exclude the possibility of a false positive.

“Different nervous system diseases have highly similar symptoms. Multiple sclerosis and neuromyelitis optica are just two examples. Even specialists experience difficulties or take a long time to diagnose them. Our technique would provide a differential diagnostic tool,” Leite said.

The next step for the group is to research biomarkers for these diseases that have not been completely mapped, including antibodies and antigens, among others. The group has begun tests for the detection of head and neck cancer.

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

A Nanobiosensor Based on 4-Hydroxyphenylpyruvate Dioxygenase Enzyme for Mesotrione Detection by P. Soto Garcia, A.L.D Moreau, J.C. Magalhaes Ierich,  A.C Araujo Vig, A.M. Higa, G.S. Oliveira, F. Camargo Abdalla, M. Hausen, & F.L. Leite. Sensors Journal, IEEE  (Volume:15 ,  Issue: 4) pp. 2106 – 2113 Date of Publication: 20 November 2014 Date of Current Version: 27 January 2015 Issue Date: April 2015  DOI 10.1109/JSEN.2014.2371773

This paper is behind a paywall.

From monitoring glucose in kidneys to climate change in trees

That headline is almost poetic but I admit It’s a bit of a stretch rhymewise, kidneys/trees. In any event, a Feb. 6, 2015 news item on Azonano describes research into monitoring the effects of climate change on trees,

Serving as a testament to the far-reaching impact of Governor Andrew M. Cuomo’s commitment to maintaining New York State’s global leadership in nanotechnology innovation, SUNY Polytechnic Institute’s Colleges of Nanoscale Science and Engineering (SUNY Poly CNSE) today announced the National Science Foundation (NSF) has awarded $837,000 to support development of a first of its kind nanoscale sensor to monitor the effects of climate change on trees.

A Feb. 5, 2015 SUNY Poly CNSE news release, which originated the news item, provides more details including information about the sensor’s link to measuring glucose in kidneys,

The NSF grant was generated through the Instrument Development for Biological Research (IDBR) program, which provides funds to develop new classes of devices for bio-related research. The NANAPHID, a novel aphid-like nanosensor, will provide real-time measurements of carbohydrates in live plant tissue. Carbohydrate levels in trees are directly connected to plant productivity, such as maple sap production and survival. The NANAPHID will enable researchers to determine the effects of a variety of environmental changes including temperature, precipitation, carbon dioxide, soil acidity, pests and pathogens. The nanosensor can also provide real-time monitoring of sugar concentration levels, which are of signficant importance in maple syrup production and apple and grape farming.

“The technology for the NANAPHID is rooted in a nanoscale sensor SUNY Poly CNSE developed to monitor glucose levels in human kidneys being prepared for transplant. Our team determined that certain adjustments would enable the sensor to provide similar monitoring for plants, and provide a critical insight to the effects of climate change on the environment,” said Dr. James Castracane, professor and head of the Nanobioscience Constellation at SUNY Polytechnic Institute. “This is a perfect example of the cycle of innovation made possible through the ongoing nanotechnology research and development at SUNY Poly CNSE’s NanoTech Complex.”

“This new sensor will be used in several field experiments on measuring sensitivity of boreal forest to climate warming. Questions about forest response to rising air and soil temperatures are extremely important for forecasting future atmospheric carbon dioxide levels, climate change and forest health,” said Dr. Andrei Lapenas, principal investigator and associate professor of climatology at the University at Albany. “At the same time, we already see some potential commercial application for NANAPHID-type sensors in agriculture, food industry and other fields. Our collaboration with SUNY Poly CNSE has been extremely productive and I look forward to continuing our work together.”

The NANAPHID project began in 2014 with a $135,000 SUNY Research Foundation Network of Excellence grant. SUNY Poly CNSE will receive $400,000 of the NSF award for the manufacturing aspects of the sensor array development and testing. The remaining funds will be shared between Dr. Lapenas and researchers Dr. Ruth Yanai (ESF), Dr. Thomas Horton (ESF), and Dr. Pamela Templer (Boston University) for data collection and analysis.

“With current technology, analyzing carbohydrates in plant tissues requires hours in the lab or more than $100 a sample if you want to send them out. And you can’t sample the same tissue twice, the sample is destroyed in the analysis,” said Dr. Yanai. “The implantable device will be cheap to produce and will provide continuous monitoring of sugar concentrations, which is orders of magnitude better in both cost and in the information provided. Research questions we never dreamed of asking before will become possible, like tracking changes in photosynthate over the course of a day or along the stem of a plant, because it’s a nondestructive assay.”

“I see incredible promise for the NANAPHID device in plant ecology. We can use the sensors at the root tip where plants give sugars to symbiotic fungi in exchange for soil nutrients,” said Dr. Horton. “Some fungi are believed to be significant carbon sinks because they produce extensive fungal networks in soils and we can use the sensors to compare the allocation of photosynthate to roots colonized by these fungi versus the allocation to less carbon demanding fungi. Further, the vast majority of these symbiotic fungi cannot be cultured in lab. These sensors will provide valuable insights into plant-microbe interactions under field conditions.”

“The creation of this new sensor will make understanding the effects of a variety of environmental changes, including climate change, on the health and productivity of forests much easier to measure,” said Dr. Templer. “For the first time, we will be able to measure concentrations of carbohydrates in living trees continuously and in real-time, expanding our ability to examine controls on photosynthesis, sap flow, carbon sequestration and other processes in forest ecosystems.”

Fascinating, eh? I wonder who made the connection between human kidneys and plants and how that person made the connection.

The Danish ‘Mini-mouth and wine

Denmark is not the first country that pops to mind when there’s mention of a nanosensor that mimics what happens in your mouth when you drink wine but that’s where the device was developed. From a Sept. 17, 2014 news item on ScienceDaily,

When wine growers turn their grapes into wine, they need to control a number of processes to bring out the desired flavour in the product that ends up in the wine bottle. An important part of the taste is known in wine terminology as astringency, and it is characteristic of the dry sensation you get in your mouth when you drink red wine in particular. It is the tannins in the wine that bring out the sensation that — otherwise beyond compare — can be likened to biting into an unripe banana. It is mixed with lots of tastes in the wine and feels both soft and dry.

Researchers at the Interdisciplinary Nanoscience Centre (iNANO ), Aarhus University, have now developed a nanosensor that is capable of measuring the effect of astringency in your mouth when you drink wine.

A Sept. 17, 2014 Aarhus University (Denmark) press release (also on EurekAlert), which originated the news item, provides a general description of the sensor,

… To put it simply, the sensor is a kind of mini-mouth that uses salivary proteins to measure the sensation that occurs in your mouth when you drink wine. The researchers are looking at how the proteins change in the interaction with the wine, and they can use this to describe the effect of the wine.

There is great potential in this – both for the wine producers and for research into the medicine of the future. Indeed, it is the first time that a sensor has been produced that not only measures the amount of proteins and molecules in your mouth when you drink wine, but also measures the effect of wine – or other substances – entering your mouth.

The wine producers’ perspective is introduced (from the news release),

The sensor makes it possible for wine producers to control the development of astringency during wine production because they can measure the level of astringency in the wine right from the beginning of the process. This can currently only be achieved when the wine is ready and only by using a professional tasting panel – with the associated risk of human inaccuracy. Using the sensor, producers can work towards the desired sensation of dryness before the wine is ready.

“We don’t want to replace the wine taster. We just want a tool that is useful in wine production. When you produce wine, you know that the finished product should have a distinct taste with a certain level of astringency. If it doesn’t work, people won’t drink the wine,” says PhD student Joana Guerreiro, first author of the scientific article in ACS NANO, which presents the sensor and its prospects.

Better Understanding of Astringency

There are many different elements in wine that create astringency, and this makes it difficult to measure because there are so many parameters. The sensor turns this upside down by measuring the molecules in your mouth instead.

“The sensor expands our understanding of the concept of astringency. The sensation arises because of the interaction between small organic molecules in the wine and proteins in your mouth. This interaction gets the proteins to change their structure and clump together. Until now, the focus has been on the clumping together that takes place fairly late in the process. With the sensor, we’ve developed a method that mimics the binding and change in the structure of the proteins, i.e. the early part of the process. It’s a more sensitive method, and it reproduces the effect of the astringency better,” says Joana Guerreiro.

There are also some technical details in the news release,

Quite specifically, the sensor is a small plate coated with nanoscale gold particles. On this plate, the researchers simulate what happens in your mouth by first adding some of the proteins contained in your saliva. After this they add the wine. The gold particles on the plate act as nano-optics and make it possible to focus a beam of light below the diffraction limit so as to precisely measure something that is very small – right down to 20 nanometres. This makes it possible to study and follow the proteins, and to see what effect the wine has. It is thereby possible to see the extent to which the small molecules have to bind together for the clumping effect on the protein to be set off.

The technique in itself is not new. What is new is using it to create a sensor that can measure an effect rather than just a number of molecules. In this case, the effect is the dry sensation you get in your mouth when you drink wine. However, it is also possible to use the sensor to measure other effects.

Here’s a look at the Mini-mouth,

PhD student Joana Guerreiro has taken part in developing a sensor, which - by using nanoscience - can measure how we experience the feeling of dryness in wine. Photo: Lars Kruse, Aarhus University.

PhD student Joana Guerreiro has taken part in developing a sensor, which – by using nanoscience – can measure how we experience the feeling of dryness in wine. Photo: Lars Kruse, Aarhus University.

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

Multifunctional Biosensor Based on Localized Surface Plasmon Resonance for Monitoring Small Molecule–Protein Interaction by Joana Rafaela Lara Guerreiro, Maj Frederiksen, Vladimir E. Bochenkov, Victor De Freitas, Maria Goreti Ferreira Sales, and Duncan Steward Sutherland. ACS Nano, 2014, 8 (8), pp 7958–7967 DOI: 10.1021/nn501962y Publication Date (Web): July 8, 2014

Copyright © 2014 American Chemical Society

This paper is behind a paywall.

ETA Sept. 19, 2014: Dexter Johnson provides some insight into the field of ‘artificial mouths’ in his Sept. 18, 2014 posting (Nanoclast blog on the IEEE [Institute of Electrical and Electronics Engineers] about the work in Denmark.

Israeli scientists help us “sniff out” bombs

A July 23, 2014 news item on ScienceDaily describes the situation regarding bombs and other explosive devices and the Israelie research,

Security forces worldwide rely on sophisticated equipment, trained personnel, and detection dogs to safeguard airports and other public areas against terrorist attacks. A revolutionary new electronic chip with nano-sized chemical sensors is about to make their job much easier.

The groundbreaking nanotechnology-inspired sensor, devised by Prof. Fernando Patolsky of Tel Aviv University’s School of Chemistry and Center for Nanoscience and Nanotechnology, and developed by the Herzliya company Tracense, picks up the scent of explosives molecules better than a detection dog’s nose. Research on the sensor was recently published in the journal Nature Communications.

Existing explosives sensors are expensive, bulky and require expert interpretation of the findings. In contrast, the new sensor is mobile, inexpensive, and identifies in real time — and with great accuracy — explosives in the air at concentrations as low as a few molecules per 1,000 trillion.

A July 23, 2014 American Friends of Tel Aviv University news release (also on EurekAlert), which originated the news item, gives more detail about the research and potential product,

“Using a single tiny chip that consists of hundreds of supersensitive sensors, we can detect ultra low traces of extremely volatile explosives in air samples, and clearly fingerprint and differentiate them from other non-hazardous materials,” said Prof. Patolsky, a top researcher in the field of nanotechnology. “In real time, it detects small molecular species in air down to concentrations of parts-per-quadrillion, which is four to five orders of magnitude more sensitive than any existing technological method, and two to three orders of magnitude more sensitive than a dog’s nose.

“This chip can also detect improvised explosives, such as TATP (triacetone triperoxide), used in suicide bombing attacks in Israel and abroad,” Prof. Patolsky added.

The clusters of nano-sized transistors used in the prototype are extremely sensitive to chemicals, which cause changes in the electrical conductance of the sensors upon surface contact. When just a single molecule of an explosive comes into contact with the sensors, it binds with them, triggering a rapid and accurate mathematical analysis of the material.

“Animals are influenced by mood, weather, state of health and working hours, the oversaturation of olfactory system, and much more,” said Prof. Patolsky. “They also cannot tell us what they smell. Automatic sensing systems are superior candidates to dogs, working at least as well or better than nature. This is not an easy task, but was achieved through the development of novel technologies such as our sensor.”

The trace detector, still in prototype, identifies several different types of explosives several meters from the source in real time. It has been tested on the explosives TNT, RDX, and HMX, used in commercial blasting and military applications, as well as peroxide-based explosives like TATP and HMTD. The latter are commonly used in homemade bombs and are very difficult to detect using existing technology.

“Our breakthrough has the potential to change the way hazardous materials are detected, and of course should provide populations with more security,” said Prof. Patolsky. “The faster, more sensitive detection of tiny amounts of explosives in the air will provide for a better and safer world.”

Tracense has invested over $10M in research and development of the device since 2007, and expects to go to market next year [2015]. Prof.Patolsky and his team of researchers are currently performing multiple and extensive field tests of prototype devices of the sensor.

Here’s a link to and a citation for a recent paper by Professor Patolsky and his team,

Supersensitive fingerprinting of explosives by chemically modified nanosensors arrays by Amir Lichtenstein, Ehud Havivi, Ronen Shacham, Ehud Hahamy, Ronit Leibovich, Alexander Pevzner, Vadim Krivitsky, Guy Davivi, Igor Presman, Roey Elnathan, Yoni Engel, Eli Flaxer, & Fernando Patolsky. Nature Communications 5, Article number: 4195 doi:10.1038/ncomms5195 Published 24 June 2014 Updated online 09 July 2014

This paper is behind a paywall but a free preview is available via ReadCube Access.

Your plant feeling stressed? Have we got a nanosensor for you!

An April 15, 2014 news item on ScienceDaily features an intriguing application for nansensors on plants that may have an important impact as we deal with the problems associated with droughts. This work comes from the University of California at San Diego (UCSD),

Biologists have succeeded in visualizing the movement within plants of a key hormone responsible for growth and resistance to drought. The achievement will allow researchers to conduct further studies to determine how the hormone helps plants respond to drought and other environmental stresses driven by the continuing increase in the atmosphere’s carbon dioxide, or CO2, concentration.

The April 15, 2014 UCSD news release by Kim McDonald, which originated the news item, describes the plant hormone being tracked and the tracking tool developed by the researchers,

The plant hormone the biologists directly tracked is abscisic acid, or ABA, which plays a major role in activating drought resistance responses of plants and in regulating plant growth under environmental stress conditions. The ABA stress hormone also controls the closing of stomata, the pores within leaves through which plants lose 95 percent of their water while taking in CO2 for growth.

Scientists already know the general role that ABA plays within plants, but by directly visualizing the hormone they can now better understand the complex interactions involving ABA when a plant is subjected to drought or other stress.

“Understanding the dynamic distribution of ABA in plants in response to environmental stimuli is of particular importance in elucidating the action of this important plant hormone,” says Julian Schroeder, a professor of biology at UC San Diego who headed the research effort. “For example, we can now investigate whether an increase in the leaf CO2 concentration that occurs every night due to respiration in leaves affects the ABA concentration in stomatal cells.”

The researchers developed what they call a “genetically-encoded reporter” in order to directly and instantaneously observe the movements of ABA within the mustard plant Arabidopsis. These reporters, called “ABAleons,” contain two differentially colored fluorescent proteins attached to an ABA-binding sensor protein. Once bound to ABA, the ABAleons change their fluorescence emission, which can be analyzed using a microscope. The researchers showed that ABA concentration changes and waves of ABA movement could be monitored in diverse tissues and individual cells over time and in response to stress.

“Using this reporter, we directly observed long distance ABA movements from the stem of a germinating seedling to the leaves and roots of the growing plant and, for the first time, we were able to determine the rate of ABA movement within the growing plant,” says Schroeder.

“Using this tool, we now can detect ABA in live plants and see how it is distributed,” says Rainer Waadt, a postdoctoral associate in Schroeder’s laboratory and the first author of the paper. “We are also able to directly see that environmental stress causes an increase in the ABA concentration in the stomatal guard cells that surround each stomatal pore. In the future, our sensors can be used to study ABA distribution in response to different stresses, including CO2 elevations, and to identify other molecules and proteins that affect the distribution of this hormone. We can also learn how fast plants respond to stresses and which tissues are important for the response.”

The researchers demonstrated that their new ABA nanosensors also function effectively as isolated proteins. This means that the sensors could be directly employed using state-of-the-art high-throughput screening platforms to screen for chemicals that could activate or enhance a drought resistance response. The scientists say such chemicals could become useful in the future for enhancing a drought resistance response, when crops experience a severe drought, like the one that occurred in the Midwest in the summer of 2012.

The scientists have provided a 1 min. 30 sec. (roughly) video where you can watch a vastly speeded up version of the process (Courtesy: UCSD),

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

FRET-based reporters for the direct visualization of abscisic acid concentration changes and distribution in Arabidopsis by Rainer Waadt, Kenichi Hitomi, Noriyuki Nishimura, Chiharu Hitomi, Stephen R Adams, Elizabeth D Getzoff, & Julian I Schroeder. eLife 2014;3:e01739 DOI: http://dx.doi.org/10.7554/eLife.01739 Published April 15, 2014

This paper is open access.

Carbon Management Canada announces research for an affordable CO2 nanosensor

Researchers at the University of Toronto (Ontario) and St. Francis Xavier University (Nova Scotia) have received funding from Carbon Management Canada (a Network Centre for Excellence [NCE]) to develop an ultra-sensitive and affordable CO2 nanosensor. From the Feb. 4, 2013 news item on Nanowerk,

Researchers at the Universities of Toronto and St. Francis Xavier are developing an affordable, energy efficient and ultra-sensitive nano-sensor that has the potential to detect even one molecule of carbon dioxide (CO2).

Current sensors used to detect CO2 at surface sites are either very expensive or they use a lot of energy. And they’re not as accurate as they could be. Improving the accuracy of measuring and monitoring stored CO2 is seen as key to winning public acceptance of carbon capture and storage as a greenhouse gas mitigation method.

With funding from Carbon Management Canada (CMC), Dr. Harry Ruda of the Centre for Nanotechnology at the University of Toronto and Dr. David Risk of St. Francis Xavier are working on single nanowire transistors that should have unprecedented sensitivity for detecting CO2 emissions.

The Carbon Management Canada (CMC) Feb. 4, 2013 news release, which originated the news item, provides  details about the funding and reasons for the research,

CMC, a national network that supports game-changing research to reduce CO2 emissions in the fossil energy industry as well as from other large stationary emitters, is providing Ruda and his team $350,000 over three years. [emphasis mine] The grant is part of CMC’s third round of funding which saw the network award $3.75 million to Canadian researchers working on eight different projects.

The sensor technology needed to monitor and validate the amount of CO2 being emitted has not kept pace with the development of other technologies required for carbon capture and storage (CCS), says Ruda.

“This is especially true when it comes to surface monitoring verification and accounting (MVA),” he says. “Improving MVA is essential to meet the potential of carbon capture and storage.”

And that’s where the ultra-sensitive sensor comes in. “It’s good for sounding the alarm but it’s also good from a regulatory point of view because you want to able to tell people to keep things to a certain level and you need sensors to ensure accurate monitoring of industrial and subsurface environments,” Ruda says.

Given CMC’s vision for ‘game-changing research to reduce carbon emissions’, it bears noting that this organization is located in Calgary (the street address ‘EEEL 403, 2500 University Drive NW Calgary‘ as per my search today [Feb.4.13] on Google [https://www.google.ca/search?q=CMC+address+Calgary&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a] suggests the University of Calgary houses the organization). Calgary is the home of the Canadian fossil fuel industry and a centre boasting many US-based fossil fuel-based companies due to its size and relative proximity to the Alberta oil sands (aka, Athabaska oil sands). From the Wikipedia essay (Note: Links and footnotes have been removed),

The Athabasca oil sands or Athabasca tar sands are large deposits of bitumen or extremely heavy crude oil, located in northeastern Alberta, Canada – roughly centred on the boomtown of Fort McMurray. These oil sands, hosted in the McMurray Formation, consist of a mixture of crude bitumen (a semi-solid form of crude oil), silica sand, clay minerals, and water. The Athabasca deposit is the largest known reservoir of crude bitumen in the world and the largest of three major oil sands deposits in Alberta, along with the nearby Peace River and Cold Lake deposits.

Together, these oil sand deposits lie under 141,000 square kilometres (54,000 sq mi) of boreal forest and muskeg (peat bogs) and contain about 1.7 trillion barrels (270×109 m3) of bitumen in-place, comparable in magnitude to the world’s total proven reserves of conventional petroleum. Although the former CEO of Shell Canada, Clive Mather, estimated Canada’s reserves to be 2 trillion barrels (320 km3) or more, the International Energy Agency (IEA) lists Canada’s reserves as being 178 billion barrels (2.83×1010 m3).

As for locating a carbon management organization in Calgary, it does make sense of a sort. Here’s a somewhat calmer description of Carbon Management Canada on the website’s About CMC page,

Carbon Management Canada CMC-NCE [Network Centre for Escellence] is a national network of academic researchers working with experts in the fossil energy industry, government, and the not-for-profit sector. Together, we are developing the technologies, the knowledge and the human capacity to radically reduce carbon dioxide emissions in the fossil energy industry and other large stationary emitters.

Carbon emissions and the growing global concern about its effects present a unique opportunity for innovation and collaboration, especially in the fossil energy industry. Rapidly increasing global complexity demands robust, responsive innovation that can only develop in a highly collaborative context involving industry, scientists, policy makers, politicians and industry leaders in concert with an informed, supportive public.

Carbon Management Canada is the national body charged with harnessing the collective energy of this diverse group in order to push forward an ambitious agenda of innovation and commercialization to bring research from the lab into the world of practice.

Funding

Funding for CMC was provided through the federal Networks of Centres of Excellence ($25 million) and the Province of Alberta through Alberta Environment ($25 million). Industry has also provided $5.7 million in contributions.

The Network has over 160 investigators at 27 Canadian academic institutions and close to 300 graduate and postdoctoral students working on research projects. CMC currently has invested $22 million in 44 research projects.

Our Themes

CMC is an interdisciplinary network with scientists working in fields that range from engineering to nanotechnology to geoscience to business to political science and communications. These investigators work in 4 themes: Recovery, Processing and Capture; Enabling and Emerging Technologies; Secure Carbon Storage; and Accelerating Appropriate Deployment of Low Carbon Emission Technologies.

Given that CMC is largely government-funded, it seems odd (almost as if they don’t want anyone to know) that the website does not feature a street address. In addition to trying  a web search, you can find the information on the last page of the 2012 annual/financial report. One final note, the chair of CMC’s board is Gordon Lambert who is also Vice President, Sustainable Development, Suncor Energy. From Suncor’s About Us webpage,

n 1967, we pioneered commercial development of Canada’s oil sands — one of the largest petroleum resource basins in the world. Since then, Suncor has grown to become a globally competitive integrated energy company with a balanced portfolio of high-quality assets, a strong balance sheet and significant growth prospects. Across our operations, we intend to achieve production of one million barrels of oil equivalent per day.

Then, there’s this on the company’s home page,

We create energy for a better world

Suncor’s vision is to be trusted stewards of valuable natural resources. Guided by our values, we will lead the way to deliver economic prosperity, improved social well-being and a healthy environment for today and tomorrow.

The difficulty I’m highlighting is the number of competing interests. Governments which are dependent on industry for producing jobs and tax dollars are also funding ‘carbon management’. The fossil fuel-dependent industry make a great deal money from fossil fuels and doesn’t have much incentive to explore carbon management as that costs money and doesn’t add to profit. Regardless of how enlightened any individuals within that industry may be they have a fundamental problem similar to an asthmatic who’s being poisoned by the medication they need to breathe. Do you get immediate relief from the medication, i.e., breathe, or do you refuse the medication which causes damage years in the future and continue struggling for air?

All of these institutions (CMC, Suncor, etc.) would have more credibility if they addressed the difficulties rather than ignoring them.

Be still my heart: e-bras and e-vests

Have they thought about the sweat? Engineers at the University of Arkansas have developed garments (a sports bra for women and a vest for men) than can monitor their physiological responses and track their location. From May 3, 2012 news release on the University of Arkanasa newswire page,

An interdisciplinary team of engineers at the University of Arkansas has developed a wireless health-monitoring system that gathers critical patient information, regardless of the patient’s location, and communicates that information in real time to a physician, hospital or the patient herself.

The system includes a series of nanostructured, textile sensors integrated into a conventional sports bra for women and vest for men. Via a lightweight and wireless module that snaps onto these garments, the sensors communicate with system software that relies on a smart phone to collect information, compress it and send it over a variety of wireless networks.

“Our e-bra enables continuous, real-time monitoring to identify any pathophysiological changes,” said Vijay Varadan, Distinguished Professor of electrical engineering. “It is a platform on which various sensors for cardiac-health monitoring are integrated into the fabric. The garment collects and transmits vital health signals to any desired location in the world.”

The system monitors blood pressure, body temperature, respiratory rate, oxygen consumption, some neural activity and all the readings provided by a conventional electrocardiograph (ECG), including the ability to display inverted T waves, which indicate the onset of cardiac arrest. The system does not require a cuff or any extra accessories to measure blood pressure and could therefore replace conventional blood-pressure monitors. It could also replace the cumbersome combination of ECG sensors and wires attached to patients while they walk on treadmills.

The researchers have provided this image,

The wireless monitoring system includes sensors, integrated into garments, that communicate health information to smart phones.

Here’s a bit more about the technology (from the May 3, 2012 news release),

The sensors, which are smaller than a dime, include gold nanowires, as well as flexible, conducting textile nanosensors. The sensors are made of arrays of gold nano-electrodes fabricated on a flexible substrate. The textile sensors are woven into the bra material. These sensors do not require conventional sticky electrodes or the use of gel.

Electrical signals and other physiological data gathered by the sensors are sent to the snap-on wireless module, the contents of which are housed in a plastic box that is slightly smaller than a ring box. As the critical wireless component, the module is essentially a low-powered laptop computer that includes an amplifier, an antenna, a printed circuit board, a microprocessor, a Bluetooth module, a battery and various sensors. The size of the module depends heavily on power consumption and minimum battery size. Varadan said that anticipated battery and Bluetooth upgrades will allow the researchers to build a smaller – 1.5 inches long, 0.75 inch wide and 0.25 inch deep – lighter and flexible module that will replace the rigid box.

Researchers are considering other applications for this technology (from the May 3, 2012 news release),

Data from the sensors then stream to commercially available cell phones and hand-held devices, which expand the use of the system beyond health care. By carrying a cell phone, athletes can monitor all signs mentioned above and other metrics, such as number of calories burned during a workout. To render clean data, the software includes filtering algorithms to mitigate problems due to motion of the hand-held device during exercise.

In light of the suggestion that this could be used by athletes I’m repeating my rhetorical question, have they thought about the sweat?

Thanks to Nanowerk where I first found out about this research at the University of Arkansas in their May 4, 2022 news item.

 

Animal love and nanotechnology

The researchers at the Fraunhofer Institute for Modular State Technologies (EMFT) have announced a nanosensor technique they’re developing to minimize the use of animals in scientific experiments. From the Jan. 10, 2012 news item on the American Association for the Advancement of Science’s (AAAS) EurekAlert,

Countless mice, rats and rabbits die every year in the name of science – and the situation is getting worse. While German laboratories used some 2.41 million animals for scientific research in 2005, by 2009 this number had grown to 2.79 million. One third were destined for fundamental biology research, and the majority were used for researching diseases and developing medical compounds and devices. People demand medicines that are safe and therapies that are tolerable, but hardly anyone is happy to accept the need for animal testing. [emphasis mine]

Yes, having read studies where they used animals for pain research (I was doing some literature searches and reading for a psychiatrist whose specialty is pain reduction [and, if possible, elimination]), I heartily concur with that last comment. Thank you to all the scientists who are working to eliminate that practice.

Since I’m not sure how long a news item remains posted on EurekAlert, I tracked down the Fraunhofer’s Research News(letter) dated 01.2012 (EMFT) for a description of what they are doing and how they are using nanosensors,

“We’re basically using a test tube to study the effects of chemicals and their potential risks. What we do is take living cells, which were isolated from human and animal tissue and grown in cell cultures, and expose them to the substance under investigation,” explains Dr. Jennifer Schmidt of the EMFT. If a given concentration of the substance is poisonous to the cell, it will die. This change in “well-being” can be rendered visible by the sensor nanoparticles developed by Dr. Schmidt and her team. (p. 5)

Specifically, here’s what they’re tracking and how they’re doing it,

Cells – the tiniest living things – that are healthy store energy in the form of adenosine triphosphate (ATP). High levels of ATP are indicative of high levels of metabolic activity in cells. If a cell is severely damaged, it becomes less active, storing less energy and consequently producing less ATP. “Our nanosensors allow us to detect adenosine triphosphate and determine the state of health of cells. This makes it possible to assess the cell-damaging effects of medical compounds or chemicals,” says Schmidt.

In order for the nanoparticles to register the ATP, researchers give them two fl uorescent dyes: a green indicator dye that is sensitive to ATP, and a red reference dye that does not change color. Next, the scientists introduce the particles to living cells and observe them under a fluorescence microscope. The degree to which the particles light up depends on the quantity of ATP present. The more yellow is visible in the overlay image, [emphasis mine] the more active are the cells. If their health were impaired, the overlay image would appear much redder. “We could in future use cancer cells to test the effectiveness of newly developed chemotherapy agents. If the nanosensors detect a low concentration of ATP in the cells, we’ll know that the new treatment is either inhibiting tumor cell growth or even killing them,” says Schmidt. “The most promising agents could then be studied further.” (p. 5)

This is the “overlay image” mentioned,

The yellow nanosensor signal in the overlay image (right) shows that the cells are active. If they were unhealthy, they would appear much redder. Center: the indicator dye signal. Left: the reference dye signal. Credit: Fraunhofer EMFT

I trust we’ll be hearing more about this research.