Category Archives: food

Living plants detect arsenic by way of embedded nanosensors

There’s a lot of arsenic in the world and it’s often a factor in making water undrinkable. When that water is used in farming It also pollutes soil and enters food-producing plants. A December 11, 2020 news item on Nanowerk announces research into arsenic detectors in plants,

Researchers have developed a living plant-based sensor that can in real-time detect and monitor levels of arsenic, a highly toxic heavy metal, in the soil. Arsenic pollution is a major threat to humans and ecosystems in many Asia Pacific countries.

Caption: Non-destructive plant nanobionic sensor embedded within leaves to report arsenic levels within plants to portable electronics, enabling real-time monitoring of arsenic uptake in living plants. Credit: Dr. Tedrick Thomas Salim Lew

I was not able to find the source for the news item but I did locate something close. From a December 13, 2020 Singapore-Massachusetts Institute of Technology (MIT) Alliance for Research and Technology (SMART), also on EurekAlert,

Scientists from the Disruptive and Sustainable Technologies for Agricultural Precision (DiSTAP) research group at the Singapore-MIT Alliance for Research and Technology (SMART), MIT’s research enterprise in Singapore, have engineered a novel type of plant nanobionic optical sensor that can detect and monitor, in real time, levels of the highly toxic heavy metal arsenic in the underground environment. This development provides significant advantages over conventional methods used to measure arsenic in the environment and will be important for both environmental monitoring and agricultural applications to safeguard food safety, as arsenic is a contaminant in many common agricultural products such as rice, vegetables, and tea leaves.

Arsenic and its compounds are a serious threat to humans and ecosystems. Long-term exposure to arsenic in humans can cause a wide range of detrimental health effects, including cardiovascular disease such as heart attack, diabetes, birth defects, severe skin lesions, and numerous cancers including those of the skin, bladder, and lung. Elevated levels of soil arsenic as a result of anthropogenic activities such as mining and smelting are also harmful to plants, inhibiting growth and resulting in substantial crop losses.

Food crops can absorb arsenic from the soil, leading to contamination of food and produce consumed by humans. Arsenic in underground environments can also contaminate groundwater and other underground water sources, the long-term consumption of which can cause severe health issues. As such, developing accurate, effective, and easy-to-deploy arsenic sensors is important to protect both the agriculture industry and wider environmental safety.

The novel optical nanosensors exhibit changes in their fluorescence intensity upon detecting arsenic. Embedded in plant tissues, with no detrimental effects on the plant, these sensors provide a nondestructive way to monitor the internal dynamics of arsenic taken up by plants from the soil. This integration of optical nanosensors within living plants enables the conversion of plants into self-powered detectors of arsenic from their natural environment, marking a significant upgrade from the time- and equipment-intensive arsenic sampling methods of current conventional methods.

“Our plant-based nanosensor is notable not only for being the first of its kind, but also for the significant advantages it confers over conventional methods of measuring arsenic levels in the below-ground environment, requiring less time, equipment, and manpower,” says Lew. “We envision that this innovation will eventually see wide use in the agriculture industry and beyond. I am grateful to SMART DiSTAP and the Temasek Life Sciences Laboratory (TLL), both of which were instrumental in idea generation and scientific discussion as well as research funding for this work.”

Besides detecting arsenic in rice and spinach, the team also used a species of fern, Pteris cretica, which can hyperaccumulate arsenic. This fern species can absorb and tolerate high levels of arsenic with no detrimental effect — engineering an ultrasensitive plant-based arsenic detector, capable of detecting very low concentrations of arsenic, as low as 0.2 parts per billion. In contrast, the regulatory limit for arsenic detectors is 10 parts per billion. Notably, the novel nanosensors can also be integrated into other species of plants. The researchers say this is the first successful demonstration of living plant-based sensors for arsenic and represents a groundbreaking advancement that could prove highly useful in both agricultural research (e.g., to monitor arsenic taken up by edible crops for food safety) and general environmental monitoring.

Previously, conventional methods of measuring arsenic levels included regular field sampling, plant tissue digestion, extraction, and analysis using mass spectrometry. These methods are time-consuming, require extensive sample treatment, and often involve the use of bulky and expensive instrumentation. The new approach couples nanoparticle sensors with plants’ natural ability to efficiently extract analytes via the roots and transport them. This allows for the detection of arsenic uptake in living plants in real time, with portable, inexpensive electronics such as a portable Raspberry Pi platform equipped with a charge-coupled device camera akin to a smartphone camera.

Co-author, DiSTAP co-lead principal investigator, and MIT Professor Michael Strano adds, “This is a hugely exciting development, as, for the first time, we have developed a nanobionic sensor that can detect arsenic — a serious environmental contaminant and potential public health threat. With its myriad advantages over older methods of arsenic detection, this novel sensor could be a game-changer, as it is not only more time-efficient, but also more accurate and easier to deploy than older methods. It will also help plant scientists in organizations such as TLL to further produce crops that resist uptake of toxic elements. Inspired by TLL’s recent efforts to create rice crops which take up less arsenic, this work is a parallel effort to further support SMART DiSTAP’s efforts in food security research, constantly innovating and developing new technological capabilities to improve Singapore’s food quality and safety.”

The research is carried out by SMART and supported by the National Research Foundation (NRF) Singapore under its Campus for Research Excellence And Technological Enterprise (CREATE) program.

Led by MIT’s Strano and Singapore co-lead principal investigator Professor Chua Nam Hai, DiSTAP is one of the five Interdisciplinary Research Groups (IRGs) in SMART. The DiSTAP program addresses deep problems in food production in Singapore and the world by developing a suite of impactful and novel analytical genetic and biosynthetic technologies. The goal is to fundamentally change how plant biosynthetic pathways are discovered, monitored, engineered, and ultimately translated to meet the global demand for food and nutrients. Scientists from MIT, TTL, Nanyang Technological University, and National University of Singapore are collaboratively developing new tools for the continuous measurement of important plant metabolites and hormones for novel discovery, deeper understanding and control of plant biosynthetic pathways in ways not yet possible, especially in the context of green leafy vegetables; leveraging these new techniques to engineer plants with highly desirable properties for global food security, including high yield density production, drought and pathogen resistance and biosynthesis of high-value commercial products; developing tools for producing hydrophobic food components in industry-relevant microbes; developing novel microbial and enzymatic technologies to produce volatile organic compounds that can protect and/or promote growth of leafy vegetables; and applying these technologies to improve urban farming.

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

Plant Nanobionic Sensors for Arsenic Detection by Tedrick Thomas Salim Lew, Minkyung Park, Jianqiao Cui, Michael S. Strano. Advanced Materials DOI: https://doi.org/10.1002/adma.202005683 First published: 26 November 2020

This paper is behind a paywall.

Food sensor made from of silk microneedles looks like velco

These sensors really do look like velcro,

The Velcro-like food sensor, made from an array of silk microneedles, can pierce through plastic packaging to sample food for signs of spoilage and bacterial contamination. Image: Felice Frankel

A September 9, 2020 news item on Nanowerk announces some research from the Massachusetts Institute (MIT),

MIT engineers have designed a Velcro-like food sensor, made from an array of silk microneedles, that pierces through plastic packaging to sample food for signs of spoilage and bacterial contamination.

The sensor’s microneedles are molded from a solution of edible proteins found in silk cocoons, and are designed to draw fluid into the back of the sensor, which is printed with two types of specialized ink. One of these “bioinks” changes color when in contact with fluid of a certain pH range, indicating that the food has spoiled; the other turns color when it senses contaminating bacteria such as pathogenic E. coli.

A Sept. 9, 2020 MIT news release (also on EurekAlert), which originated the news item, delves further into the research,

The researchers attached the sensor to a fillet of raw fish that they had injected with a solution contaminated with E. coli. After less than a day, they found that the part of the sensor that was printed with bacteria-sensing bioink turned from blue to red — a clear sign that the fish was contaminated. After a few more hours, the pH-sensitive bioink also changed color, signaling that the fish had also spoiled.

The results, published today in the journal Advanced Functional Materials, are a first step toward developing a new colorimetric sensor that can detect signs of food spoilage and contamination.

Such smart food sensors might help head off outbreaks such as the recent salmonella contamination in onions and peaches. They could also prevent consumers from throwing out food that may be past a printed expiration date, but is in fact still consumable.

“There is a lot of food that’s wasted due to lack of proper labeling, and we’re throwing food away without even knowing if it’s spoiled or not,” says Benedetto Marelli, the Paul M. Cook Career Development Assistant Professor in MIT’s Department of Civil and Environmental Engineering. “People also waste a lot of food after outbreaks, because they’re not sure if the food is actually contaminated or not. A technology like this would give confidence to the end user to not waste food.”

Marelli’s co-authors on the paper are Doyoon Kim, Yunteng Cao, Dhanushkodi Mariappan, Michael S. Bono Jr., and A. John Hart.

Silk and printing

The new food sensor is the product of a collaboration between Marelli, whose lab harnesses the properties of silk to develop new technologies, and Hart, whose group develops new manufacturing processes.

Hart recently developed a high-resolution floxography technique, realizing microscopic patterns that can enable low-cost printed electronics and sensors. Meanwhile, Marelli had developed a silk-based microneedle stamp that penetrates and delivers nutrients to plants. In conversation, the researchers wondered whether their technologies could be paired to produce a printed food sensor that monitors food safety.

“Assessing the health of food by just measuring its surface is often not good enough. At some point, Benedetto mentioned his group’s microneedle work with plants, and we realized that we could combine our expertise to make a more effective sensor,” Hart recalls.

The team looked to create a sensor that could pierce through the surface of many types of food. The design they came up with consisted of an array of microneedles made from silk.

“Silk is completely edible, nontoxic, and can be used as a food ingredient, and it’s mechanically robust enough to penetrate through a large spectrum of tissue types, like meat, peaches, and lettuce,” Marelli says.

A deeper detection

To make the new sensor, Kim first made a solution of silk fibroin, a protein extracted from moth cocoons, and poured the solution into a silicone microneedle mold. After drying, he peeled away the resulting array of microneedles, each measuring about 1.6 millimeters long and 600 microns wide — about one-third the diameter of a spaghetti strand.

The team then developed solutions for two kinds of bioink — color-changing printable polymers that can be mixed with other sensing ingredients. In this case, the researchers mixed into one bioink an antibody that is sensitive to a molecule in E. coli. When the antibody comes in contact with that molecule, it changes shape and physically pushes on the surrounding polymer, which in turn changes the way the bioink absorbs light. In this way, the bioink can change color when it senses contaminating bacteria.

The researchers made a bioink containing antibodies sensitive to E. coli, and a second bioink sensitive to pH levels that are associated with spoilage. They printed the bacteria-sensing bioink on the surface of the microneedle array, in the pattern of the letter “E,” next to which they printed the pH-sensitive bioink, as a “C.” Both letters initially appeared blue in color.

Kim then embedded pores within each microneedle to increase the array’s ability to draw up fluid via capillary action. To test the new sensor, he bought several fillets of raw fish from a local grocery store and injected each fillet with a fluid containing either E. coli, Salmonella, or the fluid without any contaminants. He stuck a sensor into each fillet. Then, he waited.

After about 16 hours, the team observed that the “E” turned from blue to red, only in the fillet contaminated with E. coli, indicating that the sensor accurately detected the bacterial antigens. After several more hours, both the “C” and “E” in all samples turned red, indicating that every fillet had spoiled.

The researchers also found their new sensor indicates contamination and spoilage faster than existing sensors that only detect pathogens on the surface of foods.

“There are many cavities and holes in food where pathogens are embedded, and surface sensors cannot detect these,” Kim says. “So we have to plug in a bit deeper to improve the reliability of the detection. Using this piercing technique, we also don’t have to open a package to inspect food quality.”

The team is looking for ways to speed up the microneedles’ absorption of fluid, as well as the bioinks’ sensing of contaminants. Once the design is optimized, they envision the sensor could be used at various stages along the supply chain, from operators in processing plants, who can use the sensors to monitor products before they are shipped out, to consumers who may choose to apply the sensors on certain foods to make sure they are safe to eat.

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

A Microneedle Technology for Sampling and Sensing Bacteria in the Food Supply Chain by Doyoon Kim, Yunteng Cao, Dhanushkodi Mariappan, Michael S. Bono Jr., A. John Hart, Benedetto Marelli. DOI: https://doi.org/10.1002/adfm.202005370 First published: 09 September 2020

This paper is behind a paywall.

Congratulations to winners of 2020 Nobel Prize for Chemistry: Dr. Emmanuelle Charpentier & Dr. Jennifer A. Doudna (CRISPR-cas9)

It’s possible there’s a more dramatic development in the field of contemporary gene-editing but it’s indisputable that CRISPR (clustered regularly interspaced short palindromic repeats) -cas9 (CRISPR-associated 9 [protein]) ranks very highly indeed.

The technique, first discovered (or developed) in 2012, has brought recognition in the form of the 2020 Nobel Prize for Chemistry to CRISPR’s two discoverers, Emanuelle Charpentier and Jennifer Doudna.

An October 7, 2020 news item on phys.org announces the news,

The Nobel Prize in chemistry went to two researchers Wednesday [October 7, 2020] for a gene-editing tool that has revolutionized science by providing a way to alter DNA, the code of life—technology already being used to try to cure a host of diseases and raise better crops and livestock.

Emmanuelle Charpentier of France and Jennifer A. Doudna of the United States won for developing CRISPR-cas9, a very simple technique for cutting a gene at a specific spot, allowing scientists to operate on flaws that are the root cause of many diseases.

“There is enormous power in this genetic tool,” said Claes Gustafsson, chair of the Nobel Committee for Chemistry.

More than 100 clinical trials are underway to study using CRISPR to treat diseases, and “many are very promising,” according to Victor Dzau, president of the [US] National Academy of Medicine.

“My greatest hope is that it’s used for good, to uncover new mysteries in biology and to benefit humankind,” said Doudna, who is affiliated with the University of California, Berkeley, and is paid by the Howard Hughes Medical Institute, which also supports The Associated Press’ Health and Science Department.

The prize-winning work has opened the door to some thorny ethical issues: When editing is done after birth, the alterations are confined to that person. Scientists fear CRISPR will be misused to make “designer babies” by altering eggs, embryos or sperm—changes that can be passed on to future generations.

Unusually for phys.org, this October 7, 2020 news item is not a simple press/news release reproduced in its entirety but a good overview of the researchers’ accomplishments and a discussion of some of the issues associated with CRISPR along with the press release at the end.

I have covered some CRISPR issues here including intellectual property (see my March 15, 2017 posting titled, “CRISPR patent decision: Harvard’s and MIT’s Broad Institute victorious—for now‘) and designer babies (as exemplified by the situation with Dr. He Jiankui; see my July 28, 2020 post titled, “July 2020 update on Dr. He Jiankui (the CRISPR twins) situation” for more details about it).

An October 7, 2020 article by Michael Grothaus for Fast Company provides a business perspective (Note: A link has been removed),

Needless to say, research by the two scientists awarded the Nobel Prize in Chemistry today has the potential to change the course of humanity. And with that potential comes lots of VC money and companies vying for patents on techniques and therapies derived from Charpentier’s and Doudna’s research.

One such company is Doudna’s Editas Medicine [according to my search, the only company associated with Doudna is Mammoth Biosciences, which she co-founded], while others include Caribou Biosciences, Intellia Therapeutics, and Casebia Therapeutics. Given the world-changing applications—and the amount of revenue such CRISPR therapies could bring in—it’s no wonder that such rivalry is often heated (and in some cases has led to lawsuits over the technology and its patents).

As Doudna explained in her book, A Crack in Creation: Gene Editing and the Unthinkable Power to Control Evolution, cowritten by Samuel H. Sternberg …, “… —but we could also have woolly mammoths, winged lizards, and unicorns.” And as for that last part, she made clear, “No, I am not kidding.”

Everybody makes mistakes and the reference to Editas Medicine is the only error I spotted. You can find out more about Mammoth Biosciences here and while Dr. Doudna’s comment, “My greatest hope is that it’s used for good, to uncover new mysteries in biology and to benefit humankind,” is laudable it would seem she wishes to profit from the discovery. Mammoth Biosciences is a for-profit company as can be seen at the end of the Mammoth Biosciences’ October 7, 2020 congratulatory news release,

About Mammoth Biosciences

Mammoth Biosciences is harnessing the diversity of nature to power the next-generation of CRISPR products. Through the discovery and development of novel CRISPR systems, the company is enabling the full potential of its platform to read and write the code of life. By leveraging its internal research and development and exclusive licensing to patents related to Cas12, Cas13, Cas14 and Casɸ, Mammoth Biosciences can provide enhanced diagnostics and genome editing for life science research, healthcare, agriculture, biodefense and more. Based in San Francisco, Mammoth Biosciences is co-founded by CRISPR pioneer Jennifer Doudna and Trevor Martin, Janice Chen, and Lucas Harrington. The firm is backed by top institutional investors [emphasis mine] including Decheng, Mayfield, NFX, and 8VC, and leading individual investors including Brook Byers, Tim Cook, and Jeff Huber.

An October 7, 2029 Nobel Prize press release, which unleashed all this interest in Doudna and Charpentier, notes this,

Prize amount: 10 million Swedish kronor, to be shared equally between the Laureates.

In Canadian money that amount is $1,492,115.03 (as of Oct. 9, 2020 12:40 PDT when I checked a currency converter).

Ordinarily there’d be a mildly caustic comment from me about business opportunities and medical research but this is a time for congratulations to both Dr. Emanuelle Charpentier and Dr. Jennifer Doudna.

Effective treatment for citrus-destroying disease?

Citrus greening is a worldwide problem. A particularly virulent disease that destroys citrus fruit, it’s a problem that is worsening. Before getting to the research from the University of California at Riverside (UCR), here’s more about the disease and how it’s developing from the UCR Huanglongbing, (HLB, Citrus Greening webpage,

The Situation: Citrus huanglongbing (HLB), previously called citrus greening disease, is one of the most destructive diseases of citrus worldwide.  Originally thought to be caused by a virus, it is now known to be caused by unculturable phloem-limited bacteria.  There are three forms of greening that have been described.  The African form produces symptoms only under cool conditions and is transmitted by the African citrus psyllid Trioza erytreae, while the Asian form prefers warmer conditions and is transmitted by the Asian citrus psyllid Diaphorina citri.  Recently a third American form transmitted by the Asian citrus psyllid was discovered in Brazil.  This American form of the disease apparently originated in China.  In North America, the psyllid vector, Diaphorina citri, of HLB is found in Florida, Louisiana, Georgia, South Carolina, Texas and Hawaii, and recently arrived in Southern California from Mexico. HLB is known to occur in Florida Lousiana, South Carolina, Georgia, Cuba, Belize and the Eastern Yucatan of Mexico.  A federal quarantine restricts all movement of citrus and other plants in the family Rutaceae from Asian Citrus Psyllid or HLB-infested areas into California in order to prevent introduction of the disease.

 Damage:  The HLB bacteria can infect most citrus cultivars, species and hybrids and even some citrus relatives.  Leaves of newly infected trees develop a blotchy mottle appearance.  On chronically infected trees, the leaves are small and exhibit asymmetrical blotchy mottling (in contrast to Zinc deficiency that causes symmetrical blotching).  Fruit from HLB-infected trees are small, lopsided, poorly colored, and contain aborted seeds. The juice from affected fruit is low in soluble solids, high in acids and abnormally bitter.  The fruit retains its green color at the navel end when mature, which is the reason for the common name “citrus greening disease.”  This fruit is of no value because of poor size and quality.  There is no cure for the disease and rapid tree removal is critical for prevention of spread.

Economic Impact: HLB is one of the most devastating diseases of citrus and since its discovery in Florida in 2005, citrus acreage in that state has declined significantly.  If the disease were to establish in California, the nursery industry would be required to move all of their production under screenhouses, pesticide treatments for the vector would be instituted resulting in greatly increased pesticide costs (3-6 treatments per year) and indirect costs due to pesticide-induced disruption of integrated pest management programs for other citrus pests.  A costly eradication program would need to be instituted to remove infected trees in order to protect the citrus industry.

Distribution of HLB: In April 2012, after about a week of testing, the California Department of Food and Agriculture (CDFA) removed a pumelo tree with a lemon graft from Hacienda Heights in Los Angeles County after the tree and an Asian citrus psyllid found on the tree both tested positive for Huanglongbing. In 2005, HLB was also found in Florida and it is now known to occur in Louisiana, Georgia, South Carolina, Cuba, Belze and Eastern Mexico.  Worldwide, HLB is also present in China, eastern and southern Africa, the Indian subcontinent, Mauritius, Reunion, the Saudi Arabian peninsula, and southeast Asia.

Research:  Research is focusing on characterization of the bacteria, development of detection methods, and control of the disease and the psyllid.  To date, control of the disease is based on planting HLB-free citrus germplasm, eradication of infected citrus plants, and control of the vector with systemic insecticides.  Countries with HLB learn to manage the disease so that they can still produce citrus.  In California, the best strategy is to keep this disease out. This goal is supported by both federal and state quarantine regulations and the University of California’s Citrus Clonal Protection Program, which provides a mechanism for the safe introduction of citrus germplasm into California.

A July 7, 2020 news item on phys.org announces what researchers hope can be used commercially as a new treatment for citrus greening disease from researchers University of California at Riverside (UCR), Note: Links have been removed,

UC Riverside scientists have found the first substance capable of controlling Citrus Greening Disease, which has devastated citrus farms in Florida and also threatens California.

The new treatment effectively kills the bacterium causing the disease with a naturally occurring molecule found in wild citrus relatives. This molecule, an antimicrobial peptide, offers numerous advantages over the antibiotics currently used to treat the disease.

UCR geneticist Hailing Jin, who discovered the cure after a five-year search, explained that unlike antibiotic sprays, the peptide is stable even when used outdoors in high heat, easy to manufacture, and safe for humans.

A July 7, 2020 UCR news release (also on EurekAlert) by Jules Bernstein, which originated the news item, provides technical detail and information about plans to commercialize the product,

“This peptide is found in the fruit of Australian finger limes, which can naturally tolerate Citrus Greening bacteria and has been consumed for hundreds of years,” Jin said. “It is much safer to use this natural plant product on agricultural crops than other synthetic chemicals.”

Currently, some growers in Florida are spraying antibiotics and pesticides in an attempt to save trees from the CLas bacterium that causes citrus greening, also known as Huanglongbing or HLB.

“Most antibiotics are temperature sensitive, so their effects are largely reduced when applied in the hot weather,” Jin said. “By contrast, this peptide is stable even when used in 130-degree heat.”

Jin found the peptide by examining plants such as the Australian finger lime known to possess natural tolerance for the bacteria that causes Citrus Greening Disease, and she isolated the genes that contribute to this innate immunity. One of these genes produces the peptide, which she then tested over the course of two years. Improvement was soon visible.

“You can see the bacteria drastically reduced, and the leaves appear healthy again only a few months after treatment,” Jin said.

Because the peptide only needs to be reapplied a few times per year, it is highly cost effective for growers. This peptide can also be developed into a vaccine to protect young healthy plants from infection, as it is able to induce the plant’s innate immunity to the bacteria.

Jin’s peptide can be applied by injection or foliage spray, and it moves systemically through plants and remains stable, which makes the effect of the treatment stronger.

The treatment will be further enhanced with proprietary injection technology made by Invaio Sciences. UC Riverside has entered into an exclusive, worldwide license agreement with Invaio, ensuring this new treatment goes exactly where it’s needed in plants.

“Invaio is enthusiastic to partner with UC Riverside and advance this innovative technology for combating the disease known as Citrus Greening or Huanglongbing,” said Invaio Chief Science Officer Gerardo Ramos. “The prospect of addressing this previously incurable and devastating crop disease, helping agricultural communities and improving the environmental impact of production is exciting and rewarding,” he said. “This is crop protection in harmony with nature.”

The need for an HLB cure is a global problem, but hits especially close to home as California produces 80 percent of all the fresh citrus in the United States, said Brian Suh, director of technology commercialization in UCR’s Office of Technology Partnerships, which helps bring university technology to market for the benefit of society through licenses, partnerships, and startup companies.

“This license to Invaio opens up the opportunity for a product to get to market faster,” Suh said. “Cutting edge research from UCR, like the peptide identified by Dr. Jin, has a tremendous amount of commercial potential and can transform the trajectory of real-world problems with these innovative solutions.”

You can find out more about Invaio Sciences here.

Citrus greening has been featured here before in an April 7, 2015 posting titled, Citrus canker, Florida, and Zinkicide. There doesn’t seem to have been much progress made with this Florida solution for citrus greening. This 2018 document on nano.gov was the most recent I could find, ZinkicideTM- a systemic nano-ZnO based bactericide/fungicide for crop protection by Swadeshmukul Santra.

3D-printed graphene sensors for highly sensitive food freshness detection

I love the opening line (lede). From a June 29, 2020 news item on Nanowerk,

Researchers dipped their new, printed sensors into tuna broth and watched the readings.

It turned out the sensors – printed with high-resolution aerosol jet printers on a flexible polymer film and tuned to test for histamine, an allergen and indicator of spoiled fish and meat – can detect histamine down to 3.41 parts per million.

The U.S. Food and Drug Administration has set histamine guidelines of 50 parts per million in fish, making the sensors more than sensitive enough to track food freshness and safety.

I find using 3D-printing techniques to produce graphene, a 2-d material, intriguing. Apparently, the technique is cheaper and offers an advantage as it allows for greater precision than other techniques (inkjet printing, chemical vapour depostion [CVD], etc.)

Here’s more detail from a June 25, 2020 Iowa State University news release (also on EurekAlert but published June 29, 2020), which originated the news item,

Making the sensor technology possible is graphene, a supermaterial that’s a carbon honeycomb just an atom thick and known for its strength, electrical conductivity, flexibility and biocompatibility. Making graphene practical on a disposable food-safety sensor is a low-cost, aerosol-jet-printing technology that’s precise enough to create the high-resolution electrodes necessary for electrochemical sensors to detect small molecules such as histamine.

“This fine resolution is important,” said Jonathan Claussen, an associate professor of mechanical engineering at Iowa State University and one of the leaders of the research project. “The closer we can print these electrode fingers, in general, the higher the sensitivity of these biosensors.”

Claussen and the other project leaders – Carmen Gomes, an associate professor of mechanical engineering at Iowa State; and Mark Hersam, the Walter P. Murphy Professor of Materials Science and Engineering at Northwestern University in Evanston, Illinois – have recently reported their sensor discovery in a paper published online by the journal 2D Materials. (…)

The paper describes how graphene electrodes were aerosol jet printed on a flexible polymer and then converted to histamine sensors by chemically binding histamine antibodies to the graphene. The antibodies specifically bind histamine molecules.

The histamine blocks electron transfer and increases electrical resistance, Gomes said. That change in resistance can be measured and recorded by the sensor.

“This histamine sensor is not only for fish,” Gomes said. “Bacteria in food produce histamine. So it can be a good indicator of the shelf life of food.”

The researchers believe the concept will work to detect other kinds of molecules, too.

“Beyond the histamine case study presented here, the (aerosol jet printing) and functionalization process can likely be generalized to a diverse range of sensing applications including environmental toxin detection, foodborne pathogen detection, wearable health monitoring, and health diagnostics,” they wrote in their research paper.

For example, by switching the antibodies bonded to the printed sensors, they could detect salmonella bacteria, or cancers or animal diseases such as avian influenza, the researchers wrote.

Claussen, Hersam and other collaborators (…) have demonstrated broader application of the technology by modifying the aerosol-jet-printed sensors to detect cytokines, or markers of inflammation. The sensors, as reported in a recent paper published by ACS Applied Materials & Interfaces, can monitor immune system function in cattle and detect deadly and contagious paratuberculosis at early stages.

Claussen, who has been working with printed graphene for years, said the sensors have another characteristic that makes them very useful: They don’t cost a lot of money and can be scaled up for mass production.

“Any food sensor has to be really cheap,” Gomes said. “You have to test a lot of food samples and you can’t add a lot of cost.”

Claussen and Gomes know something about the food industry and how it tests for food safety. Claussen is chief scientific officer and Gomes is chief research officer for NanoSpy Inc., a startup company based in the Iowa State University Research Park that sells biosensors to food processing companies.

They said the company is in the process of licensing this new histamine and cytokine sensor technology.

It, after all, is what they’re looking for in a commercial sensor. “This,” Claussen said, “is a cheap, scalable, biosensor platform.”

Here’s a link to and a citation for the two papers mentioned in the news release,

Aerosol-jet-printed graphene electrochemical histamine sensors for food safety monitoring by Kshama Parate, Cícero C Pola, Sonal V Rangnekar, Deyny L Mendivelso-Perez, Emily A Smith, Mark C Hersam, Carmen L Gomes and Jonathan C Claussen. 2D Materials, Volume 7, Number 3 DOI https://doi.org/10.1088/2053-1583/ab8919 Published 10 June 2020 • © 2020 IOP Publishing Ltd

Aerosol-Jet-Printed Graphene Immunosensor for Label-Free Cytokine Monitoring in Serum by Kshama Parate, Sonal V. Rangnekar, Dapeng Jing, Deyny L. Mendivelso-Perez, Shaowei Ding, Ethan B. Secor, Emily A. Smith, Jesse M. Hostetter, Mark C. Hersam, and Jonathan C. Claussen. ACS Appl. Mater. Interfaces 2020, 12, 7, 8592–8603 DOI: https://doi.org/10.1021/acsami.9b22183 Publication Date: February 10, 2020 Copyright © 2020 American Chemical Society

Both papers are behind paywalls.

You can find the NanoSpy website here.

Improving bacteria detection with the ‘unboil an egg’ machine

Vortex Fluidic Device (VFD) is the technical name for the more familiarly known ‘unboil an egg machine’ and, these days, it’s being used in research to improve bacteria detection. A June 23, 2020 news item on Nanowerk announces the research (Note: A link has been removed),

The versatility of the Vortex Fluidic Device (VFD), a device that famously unboiled an egg, continues to impress, with the innovative green chemistry device created at Flinders University having more than 100 applications – including the creation of a new non-toxic fluorescent dye that detects bacteria harmful to humans.

Traditional fluorescent dyes to examine bacteria viability are toxic and suffer poor photostability – but using the VFD has enabled the preparation of a new generation of aggregation-induced emission dye (AIE) luminogens using graphene oxide (GO), thanks to collaborative research between Flinders University’s Institute for NanoScale Science and Technology and the Centre for Health Technologies, University of Technology Sydney.

Using the VFD to produce GO/AIE probes with the property of high fluorescence is without precedent – with the new GO/AIE nanoprobe having 1400% brighter high fluorescent performance than AIE luminogen alone (Materials Chemistry Frontiers, “Vortex fluidic enabling and significantly boosting light intensity of graphene oxide with aggregation induced emission luminogen”).

A June 24, 2020 Flinders University [Australia] press release, which originated the news item, delves further into the work,

“It’s crucial to develop highly sensitive ways of detecting bacteria that pose a potential threat to humans at the early stage, so health sectors and governments can be informed promptly, to act quickly and efficiently,” says Flinders University researcher Professor Youhong Tang.

“Our GO/AIE nanoprobe will significantly enhance long-term tracking of bacteria to effectively control hospital infections, as well as developing new and more efficient antibacterial compounds.”

The VFD is a new type of chemical processing tool, capable of instigating chemical reactivity, enabling the controlled processing of materials such as mesoporous silica, and effective in protein folding under continuous flow, which is important in the pharmaceutical industry. It continues to impress researchers for its adaptability in green chemistry innovations.

“Developing such a deep understanding of bacterial viability is important to revise infection control policies and invent effective antibacterial compounds,” says lead author of the research, Dr Javad Tavakoli, a previous researcher from Professor Youhong Tang’s group, and now working at the University of Technology Sydney.

“The beauty of this research was developing a highly bright fluorescence dye based on graphene oxide, which has been well recognised as an effective fluorescence quenching material.”

The type of AIE luminogen was first developed in 2015 to enable long-term monitoring of bacterial viability, however, increasing its brightness to increase sensitivity and efficiency remained a difficult challenge. Previous attempts to produce AIE luminogen with high brightness proved very time-consuming, requires complex chemistry, and involves catalysts rendering their mass production expensive.

By comparison, the Vortex Fluidic Device allows swift and efficient processing beyond batch production and the potential for cost-effective commercialisation.

Increasing the fluorescent property of GO/AIE depends on the concentration of graphene oxide, the rotation speed of the VFD tube, and the water fraction in the compound – so preparing GO/AIE under the shear stress induced by the VFD’s high-speed rotating tube resulted in much brighter probes with significantly enhanced fluorescent intensities.

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

Vortex fluidic enabling and significantly boosting light intensity of graphene oxide with aggregation induced emission luminogen by Javad Tavakoli, Nikita Joseph, Clarence Chuah, Colin L. Raston and Youhong Tang. Mater. Chem. Front., [Materials Chemistry Frontiers] 2020, Advance Article DOI: https://doi.org/10.1039/D0QM00270D First published: 28 May 2020

This paper is behind a paywall.

I first marveled about the VFD (unboil an egg machine) in a March 16, 2016 posting.

Nanoparticles make home refrigeration more accessible

Periodically, academic institutions recycle news about their research. I think it happens when, for one reason or another, a piece of news (somebody was exciting) slips past with little notice. I’m glad this June 1, 2020 news item on phys.org brought this research from South Africa to my attention,

Power consumption of a home refrigerator can be cut by 29% while improving cooling capacity. Researchers replaced widely used but environmentally unfriendly R134a refrigerant with the more energy-efficient R600a dosed with multi-walled carbon nanotube nanoparticles (MWCNT). This drop-in refrigerant replacement can be deployed in the field by trained technicians, says an engineer from the University of Johannesburg.

A May 30, 2020 University of Johannesburg press release on EurekAlert, which originated the news item, provides more details about the research,

This test of nanoparticle-dosed refrigerants is a first of its kind and recently published in Energy Reports, an open-access journal. The results can help make home refrigeration more accessible for low-income families.

R134a is one of the most widely-used refrigerants in domestic and industrial refrigerators. It is safe for many applications because it is not flammable. However, it has high global warming potential, contributing to climate change. It also causes fridges, freezers and air-conditioning equipment to consume a lot of electrical energy. The energy consumption contributes even more to climate change.

Meanwhile, a more energy-efficient refrigerant can result in much lower electricity bills. For vulnerable households, energy security can be improved as a result. Improved energy economy and demand-side management can also benefit planners at power utilities, as cooling accounts for about 40% of energy demand.

Nanoparticles enhance power reduction

Nano eco-friendly refrigerants have been made with water and ethylene glycol. Previous studies showed reduced energy use in nano-refrigeration, where refrigerants were dosed with multi-walled carbon nanotube (MWCNT) nanoparticles. The nanoparticles also resulted in reduced friction and wear on appliance vapour compressors.

But previous research did not test the effects of MWCNT’s on hydro-carbon refrigerants such as R600a.

In a recent study, researchers at the University of Johannesburg tested the drop-in replacement of environmentally-unfriendly refrigerant R134a, in a home refrigerator manufactured to work with 100g R134a.

They replaced R134a with the more energy-efficient refrigerant R600a, dosed with MWCNT nanoparticles.

Reduces electricity use by more than a quarter

The researchers removed the R134a refrigerant and its compressor oil from a household fridge. They used a new refrigerant, R600a, and dosed it with multi-walled carbon nanotubes (MWCNTs). Mineral oil was used as a lubricant. The new mix was fed into the fridge and performance tests were conducted.

They found that the R600a-MWCNT refrigerant resulted in much better performance and cooling capacity for the fridge.

“The fridge cooled faster and had a much lower evaporation temperature of -11 degrees Celsius after 150 minutes. This was lower than the -8 degrees Celsius for R134a. It also exceeded the ISO 8187 standard, which requires -3 degrees Celsius at 180 minutes,” says Dr Daniel Madyira.

Dr Madyira is from the Department of Mechanical Engineering Science at the University of Johannesburg.

“Electricity usage decreased by 29% compared to using R134a. This is a significant energy efficiency gain for refrigerator users, especially for low income earners,” he adds.

To gain these advantages, the choice of MWCNT nanoparticles is critical, he says.

“The MWCNT’s need to have nanometer-scale particle size, which is extremely small. The particles also need to reduce friction and wear, prevent corrosion and clogging, and exhibit very good thermal conductivity,” says Dr Madyira.

Managing flammability

The new refrigerant mix introduces a potential risk though. Unlike R134a, R600a is flammable. On the other hand, it is more energy efficient, and it has a low Global Warming potential. Some refrigerator manufacturers have already adopted production with R600a and these appliances are available in the market.

“To do a safe drop-in replacement, no more than 150g of R600a should be used in a domestic fridge,” says Dr Madyira. “Before the replacement, the fridge used 100g of R134a gas. We replaced that with 50g to 70g of R600a, to stay within safety parameters.”

An untrained person should not attempt this drop-in replacement, says Dr Madyira. Rather, a trained refrigeration technician or technologist should do it.

Replacement procedure

“Mineral oil is used as the compressor oil. This should be mixed with the recommended concentration. A magnetic stirrer and ultrasonicator are needed to agitate and homogenize the ingredients in the mixture. The mixture can then be introduced into the compressor. After that, R600a can be charged into the refrigerator compressor, while taking care to not use more than 150g of the gas,” says Dr Madyira.

A woman’s fridge is her castle [Haven’t seen that kind of reference in many years]

A far more energy-efficient refrigerant, such as the R600a-MWCNT mix, can save consumers a lot of money. Vulnerable households in hot climates in developing countries can benefit even more.

Low income earners in many countries are dependent on home fridges and freezers to safely store bulk food supplies. This greatly reduces the risk of wasting food due to spoilage, or food poisoning due to improperly stored food. These appliances are no longer a luxury but a necessity, says Dr Madyira.

Without fridges, people may be forced to buy food daily in small quantities and at much higher prices. Because daily buying may not be required anymore, travel time and costs for buying food can be much lower as well.

Refrigeration also makes it possible to safely store more diverse food supplies, such as fresh fruit and vegetables. Medicines that require cooling can be stored at home. This can make more balanced diets and nutrition, and better physical health, more accessible for a low-income household.

Grid power still rules for low-income refrigeration

From a sustainability point of view, it can look preferable to run most home fridges and freezers from solar power.

However solar panels, backup batteries, and direct current (DC) fridges are still too expensive for most low-income families in areas served by power utilities.

Energy-efficient, alternating current (AC) fridges running on grid power may be more affordable for most. Further cutting power consumption with R600a-MWCNT refrigerant can bring down costs even more.

Refrigeration for all vs demand-side management

As more low-income households and small businesses switch on grid-powered fridges, freezers and air-conditioning, power demand needs be managed better

In South Africa where the study was conducted, the state-operated power utility faces huge challenges in meeting demand consistently. Long-lasting rolling blackouts, known as load-shedding, have been implemented as a demand-side power management measure.

Shaving off more than a quarter of the power consumption of fridges, freezers and air-conditioning units can free up national power supply for improved energy security.

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

Energy performance evaluation of R600a/MWCNT-nanolubricant as a drop-in replacement for R134a in household refrigerator system by T.O Babarinde, S.A Akinlabi, D.M Madyira. Energy Reports Volume 6, Supplement 2 ([proceedings] The 6th International Conference on Power and Energy Systems Engineering (CPESE 2019), 20–23 September 2019, Okinawa, Japan), February 2020, Pages 639-647 DOI: https://doi.org/10.101/j.egyr.2019.11.132

This paper is open access.

An artificial tongue, gold, and maple syrup

I have always imagined the love of maple syrup to be a universal love. A friend who moved to Canada from somewhere else in the world disillusioned me on that subject. She claims to be unable to grasp why anyone would love maple syrup. Should you recognize yourself in those words you may not find this post all that interesting.

However, maple syrup lovers may find this May 5, 2020 news item on Nanowerk a bit disconcerting,

It’s said that maple syrup is Quebec’s liquid gold. Now scientists at Université de Montréal have found a way to use real gold — in the form of nanoparticles — to quickly find out how the syrup tastes.

The new method — a kind of artificial tongue — is validated in a study published in Analytical Methods (“High-throughput plasmonic tongue using an aggregation assay and nonspecific interactions: classification of taste profiles in maple syrup”), the journal of the Royal Society of Chemistry, in the United Kingdom.

The “tongue” is a colorimetric test that detects changes in colour to show how a sample of maple syrup tastes. The result is visible to the naked eye in a matter of seconds and is useful to producers.

“The artificial tongue is simpler than a human tongue: it can’t distinguish the complex flavour profiles that we can detect,” said UdeM chemistry professor Jean-François Masson, who led the study. “Our device works specifically to detect flavour differences in maple syrup as it’s being produced.”

A chemistry professor at Université de Montréal has developed a new test using gold nanoparticles to establish the flavour profile of maple syrup and help producers evaluate its quality. Courtesy: Université de Montréal

There is more information but the central question as to why anyone would want an artificial tongue for tasting maple syrup is never answered (presumably they want to speed up production and ensure more consistent classification) nor is there much in the way of technical detail in a May 5, 2019 Université de Montréal news release (also on EurekAlert),

1,818 samples tested

The artificial tongue was validated by analyzing 1,818 samples of maple syrup from different regions of Quebec. The syrups that were analyzed represented the various known aromatic profiles and colours of syrup, from golden to dark brown.

“We designed the ‘tongue’ at the request of the Québec Maple Syrup Producers to detect the presence of different flavour profiles,” explained Simon Forest, the study’s first author. “The tool takes into account the product’s olfactory and taste properties.”

Maple syrup has a molecular complexity similar to that of wine. Its taste is delicate, without bitterness, and it has a subtle aroma. During the production process, specialized human tasters are employed to judge which profile each batch fits into.

“The development of the artificial tongue is intended to support the colossal work that is being done in the field to do the first sorting of syrups quickly and classify them according to their qualities,” said Masson.

Red for the best, blue for the rest

The researchers compare the artificial tongue to a pH test for a swimming pool. You simply pour a few drops of syrup into the gold nanoparticle reagent and wait about 10 seconds.

If the result stays in the red spectrum, it has the characteristics of a premium quality syrup, the kind best loved by consumers and sold in grocery stores or exported.

If, on the other hand, the test turns blue, the syrup may have a flavour “defect”, which may be treated as an industrial syrup for use in processing.

“It doesn’t mean the syrup is not good for consumption or that it has a different sugar level,” Masson said of the “blue” type syrup, which the food industry uses as a natural sweetener in other products. “It just may not have the usual desired characteristics, and so can’t be sold directly in bottles to consumers.”

60 categories of taste

Caramelized, woody, green, smoked, salty, burnt — the taste of maple syrup has as many as 60 categories to fit into. Maple syrup is essentially a concentrated sugar solution of 66 per cent sucrose and 33 per cent water; the remaining one per cent of other compounds determines the taste.

Like wine, the taste of maple syrup changes according to a variety of factors, including the harvest period, the region, production and storage methods and, of course, the weather. Too much variation in temperature over a weekend, for instance, can greatly affect the taste profile of the product.

The artificial tongue developed at UdeM could someday be adapted for tasting wine or fruit juice, Masson said, as well as be useful in a number of other agrifood contexts.

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

A high-throughput plasmonic tongue using an aggregation assay and nonspecific interactions: classification of taste profiles in maple syrup by Simon Forest, Trevor Théorêt, Julien Coutu, and Jean-Francois Masson. Anal. Methods, 2020, Advance Article DOI: https://doi.org/10.1039/C9AY01942A First published 05 May 2020

This paper is behind a paywall.

Increased food security with hexanal for younger looking, fresher tasting fruits and vegetables

Also known as an anti-aging agent for your fruit and vegetables, hexanal is an environmentally friendly chemical, which is found naturally. Research has led to a synthesized nanotechnology-enabled product now being commercialized. I’ve been following the story off and on since 2012 (see my ‘India, Sri Lanka, and Canada team up for nanotechnology-enabled food packaging‘ posting). I last wrote about the project in a December 29, 2015 posting.

For some reason, hexanal hit the news hard in 2019 having been preceded by some interest in 2018. What follows is an update and a timeline of sorts.

January 2019: More funding

A January 24,2019 essay (also published on the University of Guelph website on January 29, 2019) by Jayasankar Subramanian and Elizabeth Finnis, both are lead researchers on the the project and professors at the University of Guelph (Canada), provides an overview and an update of the hexanal project (Note: Links have been removed) ,

Fruits like mangoes, bananas, papayas and limes are shipped long distances before they get to your table. Many fruits are delicate, and there may be a long period of time that elapses between when the fruit is picked and its arrival in grocery stores and other markets. They’re often picked before they’re truly ripe in order to increase their shelf life.

Even so, globally, up to 40 per cent of all picked fruit can be lost and this represents billions of dollars. But what if we had the technology to delay fruit’s natural degradation process? This is where hexanal can make a difference.

Fruits like mangoes, bananas, papayas and limes are shipped long distances before they get to your table. Many fruits are delicate, and there may be a long period of time that elapses between when the fruit is picked and its arrival in grocery stores and other markets. They’re often picked before they’re truly ripe in order to increase their shelf life.

Even so, globally, up to 40 per cent of all picked fruit can be lost and this represents billions of dollars. But what if we had the technology to delay fruit’s natural degradation process? This is where hexanal can make a difference.

Hexanal is naturally produced by plants to ward off pests; our research at the University of Guelph has found that when it’s applied externally, hexanal can also slow down the aging process.

Like everything else, fruit ages with time. The shrivelling and rot is triggered by the enzyme phospholipase D (PLD), which causes the eventual collapse of the fruit’s membrane. Essentially, fruit membranes are snug, and function like a brick wall of phospholipid bilayers. Phospholipase D breaks the alignment of the bricks, causing the membrane to crumble. Hexanal acts by reducing and slowing the formation of PLD, which in turn slows the collapse of the fruit’s membrane.

In partnership with agricultural and social science researchers in Canada and five other countries, we have tested nine hexanal technologies. These include a spray formulation that gets applied to fruit when they’re still on trees, post-harvest dips, fruit wraps, stickers and sachets embedded with hexanal.

Our findings have implications for consumers, retailers and, more importantly, farmers. For example, when applied as a pre-harvest spray, hexanal can keep fruit on trees longer and keep it fresher after harvest — up to three weeks longer for mangoes.

Hexanal is naturally produced by all plants and is already found as an additive in some food products. Hexanal is also approved by Health Canada as a flavour formula. Our tests of synthesized hexanal sprays, dips and other technologies showed that there were no negative effects on plants, insects or other animals. In addition, hexanal evaporates within 24 hours, which means there’s no residue left on fruit.

Farmers who participated in hexanal testing in Canada and elsewhere were happy with the product both in terms of its effectiveness and bio-safety.

Currently, hexanal for agricultural use is in the two-year regulatory clearance process in Canada and the U.S. Once the process is complete, hexanal formulations are expected to be available for farmer use and can be accessed through companies with a license for production.

Hexanal slows down the ripening and aging process in fresh produce. Author provided

That’s a stunning difference, eh?

Funding

At about the same time as the Conversation essay by Subramanian and Finnis, the University of Guelph published (on the Council of Ontario Universities website) a January 27, 2019 news release announcing new funds for the project,

A University of Guelph research project that has already improved the livelihoods of small-scale Asian farmers will further expand worldwide, thanks to more than $4.2 million in federal support announced Friday afternoon.

The project involves innovative packaging developed in part by Guelph researchers using nanotechnology to improve the shelf life of mangoes, a major fruit crop in much of the world.

Already, the technology has helped to significantly reduce post-harvest losses in Sri Lanka and India. Poor storage meant that farmers routinely lost up to 40 per cent of their crops, worth upwards of $800 million a year. The new technology has also boosted per-acre revenue.

New funding support from the International Development Research Centre (IDRC) and Foreign Affairs, Trade and Development Canada will allow researchers to broaden this successful initiative to Kenya, Tanzania, and Trinidad and Tobago.

Researchers will also look at other fruit — bananas, grapes, papaya, nectarines and berries — and investigate ways to commercialize the technologies.

… it will also be a main pillar of the Guelph-East Africa Initiative, which U of G established to bring together stakeholders to support research and teaching in food, health, water, education, environment and community.

“This confirms our commitment to improve agriculture in East Africa and around the world.” [said John Livernois, interim vice-president {research} ]

The project involves the use of hexanal, a natural plant product that delays fruit ripening and aging. Guelph plant agriculture professor Gopi Paliyath holds an American patent on the discovery of hexanal as a post-harvest agent. It’s also an FDA-approved food additive.

The project also involves Guelph plant agriculture professors Paliyath and Al Sullivan; Loong-tak Lim from Food Science; and Elizabeth Finnis, Sociology and Anthropology. Foreign research partners are based at Tamil Nadu Agricultural University, India; Industrial Technical Institute, Sri Lanka; University of Nairobi, Kenya; Sokoine University of Agriculture, Tanzania; and the University of [the] West Indies, Trinidad and Tobago.

Prior to more funding: a memorandum of understanding

I’m having to guess as the document about the memorandum of understanding (MOU) to commercialize hexanal is not dated but it seems to have been produced in March 2018. (Canada’s International Development Research Centre ([IDRC] has a webpage about the memorandum but no memorandum that I could find.) I stumbled across this account of the event where the MOU was signed,

Ms. Jennifer Daubeny, Consulate General of Canada, delivered the special address narrating the significance of Canadian fundingin developing nanotechnologies to reduce post-harvest losses that enables food security in Asian Countries. Dr. K. Ramasamy, Vice Chancellor, Tamil Nadu Agricultural University [TNAU], Coimbatore presided over the function and highlighted the role of TNAU in knitting nanotechnology research framework and serving as a torch bearer in the country. He emphasized that the GAC-IDRC Project helped more than 60 students and researchers, developed two technologies, filed patents for two inventions, extensive infrastructure development besides helping more than 12,000 fruit growers in the State of Tamil Nadu. Dr. Jayasankar Subramanian, Professor, University of Guelph, Canada, explained the evolution of the project till reached the stage of technology delivery to benefit farmers. Dr. K.S. Subramanian, NABARD Chair Professor, TNAU, Coimbatore, lead Principal Investigator of the Project for India presented nanotechnologies developed to assist in the entire value chain from the farm to fork. Mr. Arun Nagarajan, President, Tamil Nadu Fruit Growers’ Association, explained that the fruit growers are eager to use the technology to improve their farm income. Mr. Terence Park, Managing Director, Smart Harvest Agri, Canada, [emphasis mine] bestowed interest to take forward the technologies to the farm gate and signed MOU with TNAU for the Commercialization of the Hexanal Formulation. Dr. G.J. Janavi,Professor & Head, Department of Nano Science & Technology, TNAU, Coimbatore welcomed the gathering and Dr. C. Sekar, Dean, Imayam Agricultural College,Turaiyur, and Co-PI of the Project proposed a formal vote of thanks.

The Canadian Consul General Ms. Jennifer Daubeny visited all the exhibits and interacted with students, scholars and researchers besides the NGO partner Myrada. She was very impressed with the technologies developed by TNAU in collaboration with University of Guelph, Canada, and looking forward to support research programs in the near future. More than 200 Scientists and Diplomats from Canada, students, scholars, university officials participated in the event.

Products launch by ITI, Colombo

Two of the project’s technology outputs -hexanal incorporated ITI Bio-wax and the Tree Fresh Formulation spray [emphasis mine] were transferred to Hayleys Agriculture Pvt. Ltd., a reputed Agro Service provider in Sri Lanka. The products were launched on 22ndMarch 2018 at the Taj Samudra Hotel, Colombo. The chief guest at the event was the Hon. Susil Premajayantha, Minister of Science Technology and Research (Min. ST&R). The guest of honour was H.E. David McKinnon, High Commissioner for Canada in Sri Lanka. Others present included the Secretary to the Min. ST&R, The Chairman and Director General, ITI, Mr Rizvi Zaheed, Hayleys Agriculture and his team, the Chairman, National Science Foundation, Sri Lanka, representative of the Chairman Sri Lanka Export Development Board, representatives from the Dialog mobile service provider, the Registrar of Pesticides, representing the Dir. Gen., of Agriculture, President of the Lanka Fruit and Vegetable Producers, Processors and Exporters Association, leading large scale mango, papaya and pineapple growers, several export and fruit processing company representatives, senior officials from the ITI, the multi-disciplinary ITI research team and our partner from CEPA. The press was also well represented and a total of 100 persons were present on this occasion. The Managing Director Hayles, the two PIs’ of the project, the High Commissioner for Canada, The Minister and for ST&R and the Secretary to the Ministry addressed the gathering and the new video clip on the project was viewed. The new products were jointly uncovered for display by the Hon. Minister and H.E., the High Commissioner. Samples of the products were distributed to the President of the Lanka Fruit and Vegetable Producers Processors and Exporters Association and to two leading mango growers. The Project team also took this opportunity to run a presentation on the various stages of the project and related activities, display posters on their research findings and to print and distribute the pamphlets on the same as well as on hexanal, the latter as prepared by our partners from the University of Guelph. The launch ended with a time of fellowship providing a useful opportunity for networking.

A YouTube video about the product launch of hexanal-based Bio-wax and the Tree Fresh Formulation spray (I don’t know if those were the permanent names or if they are specific to Sri Lanka and other countries will adopt other names) helped to establish the date for the MOU. You can find the video here.

Judging from the media stories, the team in India has provided most of the leadership for commercializing hexanal.

Commercialization 2019 and beyond

To sum up, after a memorandum of understanding is signed and some prototype products have been unveiled in India in 2018 then, in early 2019, there’s more funding announced by IDRC to expand the number of countries involved and to continue research into efforts to save other types of produce.

Moving things along is an August 15, 2019 news item on Agropages.com,

Two nano formulations would be commercialized by the Directorate of Agri business development of Tamil Nadu Agricultural University (TNAU) soon.  

Fruity fresh is a liquid nano formulation containing hexanal that keeps fruits and vegetables fresh for more days. The pre-harvest spray of Fruity Fresh extends the shelf life of mango for two weeks on trees and another two weeks under storage conditions by employing post-harvest dip methodology, Dr. A. Lakshmanan, Professor and Head, Department of Nano Science and Technology told a meet on “Linking Nano Stakeholders” held at the University.  

Hexanal has also been successfully encapsulated in polymer matrix either as an electro spun fibre matrix (Nano sticker) or nano-pellets that extends shelf life of fruits by 1-2 weeks during storage and transportation, he said.  

This sticker and pellets technology is highly user friendly and can be placed inside the cartons containing fruits during transport for enhancing the freshness.

According to a November 5, 2019 article by Pearly Neo for foodnavigator-asia.com, there is pricing for four products. Nano Sticker and Nano Pellet each will cost $US 0.028 and the spray, Fruity Fresh, will cost $US 4.23 to $US 5.65 for a one liter bottle diluted in 50 liters of water (for use on approximately five trees) and the Fruity Fresh dipping solution at $US 0.0071per kg.

As far as I’m aware none of these products are available in Canada but there is a website for Smart Harvest Agri, Canada although the name used is a little different. First, there’s the Federal Corporation Information listing for Smart Harvest Agritech Limited. You’ll notice there are two directors,

Amanjit Singh Bains
7685 150B Street
Surrey BC V3S 5P1
Canada

Terence Park
Yongsan CJ Nine Park
Seoul
Korea, Republic of

The company’s Smart Harvest website doesn’t list any products but it does discuss something they call “FRESHXtend technology” for fruits and vegetables.

Final comment

I sometimes hear complaints about government funding and what seems to be a lack of follow through with exciting research work being done in Canada. I hope that in the months to come that this story of an international collaboration, which started with three countries and has now expanded to at least six countries and has led to increased food security with an environmentally friendly material and commercialization of research, gets some attention.

From the few sources I’ve been able to find, it seems India and Sri Lanka are leading the commercialization charge while Canada has contributed to an Asian-led project which has now expanded to include Kenya, Tanzania, and Trinidad and Tobago. Bravo t them all!