Millions of tons of lignin—a biopolymer that strengthens the cell walls of plants—are produced each year by the pulp and paper industry. Although lignin production is widescale, lignin is considered a waste product with no commercial application due to its complexity as a non-uniform material. Incorporation of lignin into commercially important polymers remains a challenge in both pure research and applied industrial environments; yet if we could understand and use this material in a predictable manner, it would have a myriad of applications. Fortunately, a 2018 study in ACS Sustainable Chemistry & Engineering has revealed how to prepare and characterize different copolymers of lignin and polylactide (PLA).
Tag Archives: chemistry
Researchers uncover how to make better polymers from pulp and paper waste
Posted in Science Communication
Tagged biodegradable, biopolymers, chemistry, copolymer, copolymers, green, green chemistry, lignin, materials, Materials Chemistry, melt, Outreach Project, PLA, polymers, Public Engagement, UBC
Plastic replacements: some new conSQUIDerations
The amount of plastic that has been produced to date now exceeds 8300 million metric tonnes (Mt). To put this into perspective, the average blue whale weighs approximately 180 Mt, thus 46 million blue whale’s worth of plastic has been produced since humans started commercializing plastics in 1950. Our society had become extremely dependent on plastic products and synthetic (petroleum- based) textiles which cause serious consequences such as microplastic and microfiber pollution as I’ve discussed in previous blog posts.
Figure 1. Size reference for blue whales. Wikipedia Commons
Bioplastics have more recently taken the stage as a potential avenue for replacing petroleum-based plastics. Biologically based polymers have structural elements such as helices, β-turns, β-sheets and coils which provide structural integrity and resilience and can replicate the desirable polymeric interactions in plastics. Additionally, a lot of new material is being developed based on the protein polymers that are naturally occurring in biological systems (including ourselves).
Figure 2. Fibrous protein polymers have molecular architecture that can include (i) helices and coils, (ii) β-turns and β-spirals, and (iii) β-sheets. Source
Video 1. SRT- coated fabrics that self-heal in water.
Squid ring teeth (SRT) are an especially promising candidate for making functional fibres and films due to its strength, conductivity and self-healing properties. The SRT are located inside the suction cups of the tentacles of squids and are composed of a naturally occurring protein complex. Fortunately, it is not necessary to harvest squid to obtain the SRT proteins as they can be biosynthetically produced since having their genome sequenced. The SRT-inspired monomer is repeated to create a polymeric chain and the resulting protein that is produced is named accordingly as tandem repeat (TR) proteins.
Figure 3. The Squid ring teeth of a giant squid. Wikipedia Commons
Figure 4. Optical images of squid ring teeth (SRT) and the six common squid species they originate from. Source
Films produced with SRT proteins consist of disordered domains that provide elasticity and flexibility to the materials in addition to ordered domains such as β-sheets that provide mechanical strength. One study designed four TR proteins denoted as TR-nX where X was the number of repeat units within the molecule. They measured the mechanical force of these four TR proteins and found that the ultimate strength of the protein’s scale linearly, with TR-n25 reaching an ultimate strength of 40 MPa. As seen in Figure 4 below, there is a limitation of the study due to sample size. The error bars of the TR-n12 and TR-n25 overlap, so it is not possible to say there is a statistically significant difference from each other.
Figure 4. Mechanical testing of fully hydrated TR proteins (inset shows 1/n dependence) Source
Additionally, SRT protein films have been suggested as a potential solution to the issues related to the release of microfibers into the water from washing. A cloth made from polyester was coated with an SRT protein film and was found to dramatically increase the cloths resistance to abrasion (and microfiber release) compared to cloths that were not coated with SRT protein films.
While there is still a lot of further research to be done, SRT-based proteins are a promising avenue for making our world a little bit less plastic.
~Isla
Posted in Biological Sciences, Science Communication
Tagged biological chemistry, chemistry, microplastic, plastic, pollution, polymers, protein, squid, technology
Drug Sponge: Absorbing up the problems
https://www.youtube.com/watch?v=fQsYw5brVw8&t=7s
Chemotherapy is a well-known treatment for cancer, using drugs to destroy cancer cells. However, doctors administrate these anticancer drugs with caution because they are also considered poisonous. After cancer treatments, excess drugs can stay in the human body, causing damage to healthy cells, resulting in unwanted toxic side effects. What if there was something that can absorb these drugs like a portable filter?
Various chemotherapy treatments on the growth of mesenchymal stem cells (MSC). MSC is found in bone marrow cells, that contribute to regenerating bone and muscle tissues. Source
Dr. Steven Hetts from the University of California Berkeley initially thought of an idea, to introduce a sponge-like polymer that can absorb excess chemotherapy drugs. Sponges have immensely grown in popularity in the pharmaceutical field, as the metabolites produced hold biologically active natural products. Approximately 5300 different natural products extracted from sponges have shown pharmaceutical properties, such as anticancer and antibacterial active properties.
Schematic diagram of the developed 3D printed porous absorber. Source
In early 2019, he shared this concept among researchers from other American universities, eventually publishing a paper that describes the development of a porous absorbent polymer. The researchers built the lattice structure using 3D printing that allows the blood to circulate through the bloodstream. In addition, they coated the polymer with a polystyrenesulfonate copolymer, essential for absorbing the chemotherapy drug, doxorubicin.
Doxorubicin: a chemotherapy medication used to treat cancer. Source: Wikimedia Commons
This innovative biomedical device showed great promise, as the polymer efficiently absorbed 64±6% of the drug. Even though this was tested on pigs with healthy livers, the understanding of this device allows researchers to focus on improvements. Lattice size, the type of coating, the thickness of the coating, and the number of absorbers are all possible approaches to a more effective drug sponge.
With this in mind, doctors can potentially administrate higher doses of drugs for more aggressive tumors. In addition, modifications to the drug sponge’s coating can absorb other types of powerful chemotherapy drugs. Although testings on humans are not yet approved by the FDA, the drug sponge is a huge step towards minimizing chemotherapy toxic side effects.
Posted in Issues in Science, Science in the News
Tagged Biochemistry, chemistry, drug sponge, Pharmaceuticals
Photoactivated Self-healing Copolymers- It’s Lit
A scratch on your car may no longer need a trip to the auto-shop. Simply applying heat or light could remedy this issue. This idea could soon be a reality using vitrimers, a new class of plastics that have thermal and chemical stability, but can also be self-healing on a small scale and fully recyclable on a larger scale.
Taylor Wright from Dr. Wolf’s group at UBC. Source
In 2018, at the University of British Columbia, Taylor Wright under the supervision of Dr. Michael Wolf investigated the photoactive self-healing properties of vitrimeric copolymers.
Photoactive materials undergo physical and chemical changes in response to illumination. The development of responsive materials to both heat and light were explored for the first time through the incorporation of functional molecular groups into the polymeric backbone of these systems.
Wright and Wolf’s focus on the molecule’s response to light also offered a new aspect into vitrimeric research compared to the previous studies, that exclusively focused on the vitrimers’ response to heat.
Figure 1. Comparison of thermoplastics and thermosets upon heating. Source
So what exactly are vitrimers? Vitrimers are a new class of polymeric material that was first created in 2011 by a Polish physicist, Dr. Ludwik Leibler. By combining characteristics of thermosets and thermoplastics, Leibler was able to develop a material that is strong and durable, yet moldable and recyclable.
Thermoplastics are made of plastics linked by intermolecular forces. They can be easily molded and shaped under heat, then cooled down to produce the final structure. This allows for ease when it comes to processing. Additionally, this property allows them to be recycled to produce new products.
Conversely, thermosets involve irreversible cross-linking, connecting the backbones of the polymer chains with molecular bridges. This results in enhanced chemical and heat resistance, making the material less susceptible to stress-cracking. However, due to their cross-linked bonds, these materials do not melt upon exposure to heat, unable to remold and recycle.
Vitrimers combine the best properties of both materials; structural integrity is improved through cross-linking, as well as self-healing and fully recyclable properties.
Figure 2. The molecular structure of the photoactivated vitrimeric copolymer created by Wright and Wolf. Source
As seen above in Figure 2, the vertical wiggly line splits the system into the two unique parts that make this a copolymer. The left side shows the aromatic anthracene molecule that crosslinks into a dimer in response to UV radiation. The amine on the right side behaves like a more traditional vitrimer and responds to heat to form reversible exchanges.
Originally, their aim was to create a single polymeric system that responds to both heat and light simultaneously. However, during their research, they found that amines directly bonded to the anthracene molecules simply do not engage in the bond exchange process. They believed the electronics of the ring alters the behaviour of the molecule in comparison with non-aromatic amines.
Studying the photodimerization and thermally exchangeable functionalities of the copolymer based on the vinylogous urethane vitrimer, the self-healable properties can be seen in the video above. Self- healing polymers are a class of materials that enable the repair of micro-scale damage in the coating, ultimately restoring the passive state of the metal substance. This enables reprocessability or longer lifetimes in cross-linked polymeric materials. The systems containing anthracene undergo self-healing through reversible reactions, allowing monomers and polymer chains to link and unlink.
Figure 3. Polymer sample, P2, mounted on a glass slide. A scratch from a razor blade can be observed. Source
Wright and Wolf tested the modification of surface properties by using a razor blade to scratch a polymer sample (that Wright denoted as P2), that was mounted on a glass slide. By using optical microscopy, the scratches were observed as dark lines crossing the sample, as seen below in Figure 4. The scratches were seen to decrease in width and ultimately close during heating through a series of expansions and contractions of the material, which can be seen in the video above.
Figure 4. Optical microscope image of (a) sample P2a initial scratch, (b) P2a after heating (c) sample P2b initial scratch, (d) and (e) P2b after heating. Black scale bar is 300 μm. Source
These specific Wright and Wolf vitrimeric copolymers will not be scaled up for commercial use, due to the difficulties of incorporating the two components of the copolymer together. However, the general idea of vitrimeric materials has “almost limitless applications”. For example, they can be incorporated into products that have a long lifetime, such as shipping materials and plastic stadium seats which can be recycled into new products once they start to deteriorate.
Additionally, Wright is currently working on vitrimers that start as a viscous liquid, much like thermoplastics, that can be easily molded and processed. This possible advancement will provide more flexibility with processing the starting material and ease in the synthesis process.
~Brina, Isla and Taiki (Group 4)
Posted in Science Communication
Tagged chemistry, Outreach Project, plastic, pollution, polymers, science, technology
New technology might allow mammals to have super-visual capabilities in the future
Radio waves, gamma rays, visible light, and all the other parts of the electromagnetic spectrum are electromagnetic radiation. However, a typical mammalian eye can only respond to visible light, which is a small portion (<1%) of the electromagnetic spectrum. But a recent study shows a new technology that may enable humans to sense near-infrared light.
The electromagnetic spectrum. Retrieved from Wikipedia Common.
The group of Professor Tian Xue from the University of Science and Technology of China and the group of Professor Gang Han from the University of Massachusetts State University have for the first time achieved the naked-eye infrared light perception in mice. Mice were able to see near-infrared light after being injected with special nanoparticles into their eyes. The special nanoparticles named pbUCNPs can anchor tightly on the retinal photoreceptors of mice and convert near-infrared light into visible green light. Additionally, these nanoparticles can stay in the eye for over two months without any obvious side effect.
The injection of the nanoparticles into the eyes of the mice. Image created by Ma et al.
Xue said: “This research breaks through the limitations of traditional near-infrared spectroscopy and develops a naked-eye passive infrared vision expansion technology, suggesting that humans have the potential for super-visual capabilities.”
To prove that the injected mice could see near-infrared light, the scientists did two experiments.
One experiment called pupillary light reflex. The pupillary light reflex gives the constriction of pupils in response to stimulation of eyes by light. The researchers shined near-infrared light into the eyes of injected and non-injected mice. The pupils of the injected mice constricted, while the non-injected mice showed no response.
pbUNCPs allow for detection of near-infrared (NIR) light. (A) Images show only the mouse injected with pbUCNPs gives a reflex when exposed to NIR light (980 nm), indicating that pbUCNP-injected mice are able to sense NIR light. (B) The curve shows the more intensive the NIR light is, the greater the pupil constriction response. Data are mean±SD. (Ma et al., 2019)
In the second experiment, as mice prefer to stay in the dark, the researches designed a box with two connected compartments. One compartment was completely dark, and the other was illuminated with near-infrared light. Scientists observed that the injected mice spent more time in the dark compartment, while the non-injected mice spent similar amounts of time in both compartments.
The set-up of the Light-Dark Box. (Ma et al., 2019)
pbUCNP-injected mice recognize and respond to NIR light. Control mice and those injected with pbUCNPs responded to visible light (525 nm). However, when the light was in the NIR range (980 nm), only mice injected with pbUCNPs responded. Data are mean±SD. (Ma et al., 2019)
These two experiments proved that the injected mice perceived near-infrared light. Moreover, the scientists showed that the nanoparticles would not affect the normal vision of the injected mice.
This technique can potentially be applied to humans not only for generating super vision but also for repairing visible spectrum defects, such as colour blindness.
Wenxin Zhao
Is it actually 100% oregano?
Have you ever wondered what is in the food you eat? This pizza may contain additional ingredients that you may not be aware of.
A homemade pita bread pizza, garnished with oregano. Geoff Peters from Vancouver, BC, Canada, Creative Commons Attribution 2.0 Generic (CC BY 2.0), Homemade Pita Pizza (5206619742).jpg
According to Canadian Food Inspection Agency (CFIA), food fraud is an emerging global issue. In fact, food fraud “may cost the global food industry $10 to $15 billion per year”. Examples of food fraud may include substitution/addition of ingredients or tampering/mislabeling of food packages, and selling these inferior products at a higher price for profit. Food fraud is problematic; therefore, it is crucial that CFIA and the food industry combat food fraud to protect consumer safety.
However, in 2016, there has been a report of adulterated dried oregano in Australia. Some brands that declare “100% oregano” only have 33% – 50% of actual oregano. The remaining percentage could contain additional olive and myrtle leaves as fillers. The presence of olive and myrtle leaves can pose a health risk, because it can carry a higher amount of pesticides, which can contaminate the dried oregano. Therefore, it is important to find a way to detect these fillers, so that they can be eliminated from the market.
An example of dried oregano. Henna, Creative Commons Attribution-ShareAlike 1.0 Generic (CC BY-SA 1.0), Oregano-spice.jpg
An example of myrtle leaves. division, CSIRO, Creative Commons Attribution 3.0 Unported (CC BY 3.0), CSIRO ScienceImage 3022 Dried Lemon Myrtle Leaves Backhousia citriodora.jpg
An example of dried myrtle leaves. division, CSIRO, Creative Commons Attribution 3.0 Unported (CC BY 3.0), CSIRO ScienceImage 4242 Dried and Crushed Lemon Myrtle Leaves Backhousia citriodora.jpg
An olive branch. Hans Bernhard (Schnobby), Creative Commons Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0), Olive branch.jpg
Recently, a paper from the journal of Food Chemistry published in 2019, suggests that GC-MS (a common instrument in a Chemistry lab) can be used to detect and measure the amount of pesticides in adulterated oregano samples. By identifying the most predominant pesticides in adulterated oregano, the pesticides can be used as potential markers for identifying adulterated oregano.
But how does GC-MS work? In the “GC” part of the instrument, the pesticides travel through the column, in different speeds, based on its unique chemical properties. Once all of the pesticides are separated, they go through the “MS” part of the instrument, where they get fragmented by a beam of electrons before it travels through the mass analyzer and reaches to the detector for data collecting (see image below).
A schematic of the GS-MS instrument. Detector is attached to the right side of the mass analyzer (not shown). Cwszot, Kkmurray, Creative Commons Attribution 2.5 Generic (CC BY 2.5), Electron ionization GC-MS.png
As a result, pesticides (cyfluthrin (sum), cyhalothrin lambda, and pyriproxfen) are present in higher quantity in the 34 adulterated oregano samples than in the 42 genuine samples. Therefore, cyfluthrin, cyhalothrin lambda, and pyriproxfen could be used as potential markers for detecting adulterated oregano.
Graph from the research paper. Click on the image for high-definition. Drabova et al., Creative Commons Attribution 4.0 International (CC BY 4.0), Adapted from Figure 5 in Food fraud in oregano: Pesticide residues as adulteration markers
In conclusion, it is possible to identify the adulterated samples by using a chemical technique to stop food fraud. Although CFIA and food industries work to protect consumers from food fraud, CFIA suggests a few ways for consumers to identify food fraud.
But as for me, I will stick to growing my own oregano in my backyard.
Updated: March 28, 2019
Reference:
Canadian Food Inspection Agency. The CFIA Chronicle. http://www.inspection.gc.ca/about-the-cfia/the-cfia-chronicle-fall-2017/food-fraud/eng/1508953954414/1508953954796 (accessed Mar 08, 2019).
Canadian Food Inspection Agency. Food fraud. http://www.inspection.gc.ca/food/information-for-consumers/food-safety-system/food-fraud/eng/1548444446366/1548444516192 (accessed Mar 08, 2019).
Canadian Food Inspection Agency. Types of food fraud. http://www.inspection.gc.ca/food/information-for-consumers/food-safety-system/food-fraud/types-of-food-fraud/eng/1548444652094/1548444676109 (accessed Mar 08, 2019).
The Sydney Morning Herald. Food Fraud: Popular oregano brands selling adulterated products. https://www.smh.com.au/business/consumer-affairs/food-fraud-popular-oregano-brands-selling-adulterated-products-20160405-gnygjo.html (accessed Mar 08, 2019).
Drabova, L., Alvarez-Rivera, G., Suchanova, M., Schusterova, D., Pulkrabova, J., Tomaniova, M., . . . Hajslova, J. Food fraud in oregano: Pesticide residues as adulteration markers. Food Chemistry. [Online] 2019, 276, 726-734. doi:10.1016/j.foodchem.2018.09.143 (accessed Mar 08, 2019).
Canadian Food Inspection Agency. How food fraud impacts consumers. http://www.inspection.gc.ca/food/information-for-consumers/food-safety-system/food-fraud/how-food-fraud-impacts-consumers/eng/1548444986322/1548445033398
Posted in Science in the News, Uncategorized
Tagged Analytical Chemistry, chemistry, Science & Food
Polyester Suits: a Fashion and Environmental Faux Pas
Although polyester suits are no longer a fashion statement like they were in the ’70s, polyester and other synthetic materials such as nylon are still very popular materials used to make clothes due to their accessibility, durability and cost-effectiveness. Polyester, nylon and acrylic fibers are among the most popular synthetic fibers on the market. As their name would imply, synthetic fibers are manmade, synthesized fibers and are petroleum-based products.
Figure 1: The manufacturing process of synthetic nylon fibers. Source: Japan Chemical Fibers Association
One of the advantages and appeals of synthetic fibers is that they can be made using recycled materials. This recycled material can be old polyester materials themselves or can even be old plastic water bottles or other recyclable plastic products. There are many companies actively working to use recycled materials to make their apparel and while this may seem beneficial and an excellent solution to fully utilize plastic products to their full potential, it may actually be a double-edged sword. More people could be inclined to use plastic products, as they would assume that the plastic will be recycled properly. Unfortunately, that is not often the case. Not all the plastic products on the market are recycled responsibly and instead can contribute even more to the growing plastic pollution and microplastic issue as mentioned in my previous post. But even when plastic IS effectively recycled to make new fabric, there still is another hidden micro problem, a microfiber problem.
Figure 2: The cycle of synthetic polyester apparel made from recycled materials. Source: Japan Chemical Fibers Association
The video above outlines the not so micro issue surrounding microfibers.
Essentially, every time you wash a piece of clothing made of synthetic materials, tiny fibers or pieces of plastic, called microfibers are released. These microfibers are a type of microplastic since they are essentially micro pieces of plastic. It causes an issue due to the microfibers being too small and bypassing the filters in both our washing machines and at water waste treatment sites.
Figure 3: The estimated amount of fibers released from every wash for three synthetic fibers commonly used in the textile industry. Source for data.
This study estimates the amount of microfibers released (in mg) after the first five washes of 6 kg (the weight of a typical load of laundry) of three different types of commonly used synthetic materials. Figure 4 illustrates the data from their study. While looking at this data, it can be concluded that after the first five washes, the number of microfibers released decreases. However, other studies conclude the opposite—that the amount of microfibers released actually increases the more that the clothing items are washed due to the degradation of the product and the loss of structural integrity.
Figure 4: The amount of fibers (in mg) released from washing 6 kg of synthetic material. Source for data.
So, what can be done to mitigate the amount of microfibers entering our waterways and contributing to the alarming microplastics issue? Some studies suggest implementing better, higher quality filters in waste treatment plants and found them to be extremely effective at trapping these microfibers, decreasing the amount of microplastics entering waterways by 98%. Additionally, there have been other suggestions that include using proteins found in squids to make a biomaterial that can be used to make fabrics. The simplest solution, however, is to just be more conscientious about the products you purchase. By looking for products that have blends of both synthetic and natural fibers not only can recycled materials be incorporated, but also the integrity of the fabrics is improved to prevent less microfiber shedding, leading to the best of both worlds.
~Isla
Posted in Issues in Science
Tagged chemistry, microfiber, microplastic, plastic, pollution
Are artificial sweeteners the better alternative?
Currently, there are many sugar substitutes that replace table sugar. They give the desired sweetening taste while providing fewer calories. The Food and Drug Administration (FDA) regulate and approve sugar alternatives that meet the criteria.
Sweetener prices with relative to sugar. Adapted from Sugar and Sweetener Guide
In addition, many sweeteners are a lot cheaper, and still provide the same sweetness as table sugar. Although these substances are generally recognized as safe, consuming artificial sweeteners have some drawbacks to one’s health. Recently there has been news that shows the products are perhaps more dangerous than beneficial.
Neotame chemical structure. Source: Wikimedia
Artificial sweeteners require an Acceptable Daily Intake (ADI), informing how much of that substance an individual can take daily, without the risk of receiving toxic effects. Neotame, a recently approved sweetener by the FDA, has an extremely low ADI level of 0.3 mg/kg. Even though it has sweetness 7000-13000 times more than table sugar, it is still approved because there are no deadly effects.
In 2017, research by many researchers in the United States further investigated the effects of neotame, on a mice’s gut microbiota in their digestive system. After four weeks, the mice that consumed neotame (dose level of 0.75 mg/kg) experienced decreased levels of malic acid and glyceric acid, both important acidic components to aid food digestion. In addition, fecal metabolism exhibited decreased activity, causing the concentrations of fatty acids, lipids, and cholesterol levels to rise. This shows how neotame can harm our digestive system in the long run.
A collection of soft drinks. Source: Flickr
For sugar alternatives in soft drinks, people are stating that the only real side effect of no-calorie sweeteners is the tendency to eat even more. This won’t happen immediately, but several studies claim that soft drinks will eventually lead to weight gain. At the same time, another study showed the consumption of sugar-sweetened beverages in the United States was linked to a 121% increase in type 2 diabetes. Even though the sweetness is there, people’s appetite won’t be satisfied until the calories are consumed, ironically leading to a craving for more food.
Examples of other sugar alternatives. Source
Sugar substitutes are still common to use for many because of their lost cost, adding little to no calories to a daily diet. There is no way one can completely avoid sugar consumption, for sugar is essential energy to our body. Instead, consumers should be more aware of what sugar substitutes they are consuming while reducing sugar intake, to stay as healthy as possible.
-Taiki Matsumoto
Posted in Issues in Science
Tagged artificial sweetener, biological chemistry, chemistry, food science
Is Machine Learning the Future of Technology Development and Chemistry Research?
The ability for scientist to develop new drugs for everything from rare diseases to headaches is often reliant on precedent and systematic investigations. These methods are often costly and time consuming. Similar problems arise in development of new materials that may enhance our energy production. Our limited ability to rationally design materials hampers their development. This leads to reliance on our ability to recognize the trends and behavior of already existing materials. However, what if we could amplify the ability to recognize patterns beyond human limits? Machine learning answers this problem.
A graph depicting the general algorithm machine learning follows. Source: Wikimedia Commons
While machine learning is a form artificial intelligence, our jobs are safe. Machine learning is the use of statistics and the power of computers to predict results or identify trends in data. The general method relies on the input of “training” data which is analyzed using statistics. After developing a model, information may be inferred from new data the computer encounters.
-Video Source: Google Cloud Platform educational AI Adventures Series on YouTube by Yufeng Guo in 2017.
Large technology companies have recognized the advantage of integrating machine learning into technology development. Google is one example that has successfully introduced it. Gmail uses machine learning to service 1.5 billion active accounts. They claim to detect 99.9% of phishing and spam mail from entering the user’s inbox. However, machine learning is not limited to technology companies. Chemistry researchers have quickly adopted it.
Total Number of Chemistry Publications with “Machine Learning” in Title
Starting in 1969, the first chemistry journal article with “machine learning” in the title was published. By combining machine learning with a common technique called mass spectrometry, Peter Jurs at the University of Washington was able to determine chemical composition of “unknown” chemicals using the input of 348 unique patterns as “training” data.
More recently there has been an almost exponential increase in the number of chemistry publications applying machine learning. In the last two years approximately 6 times as many publications were made than in the past 48 years. Tommi Jaakkola, a Professor of Electrical Engineering and Computer Science at MIT said at a consortium about implementing machine learning in the pharmaceutical industry: “by marrying chemical insights with modern machine learning concepts and methods, we are opening new avenues for designing, understanding, optimizing, and synthesizing drugs.” The materials science community has also seen integration with the development of novel long chained molecules called polymers for photovoltaics by scientist at Osaka University. Shinji Nagasawa, the lead author explained the importance: “there’s no easy way to design polymers with improved properties. Traditional chemical knowledge isn’t enough. Instead, we used artificial intelligence to guide the design process.”
Solar cell efficiency over years showing a substantial increase. Source: Wikimedia Commons
While machine learning is not the solution to all chemical problems or spam mail, it is being widely accepted by the scientific community and technology industry for good reasons. Even with limitations, it’s effectiveness across a wide array of industry and research emphasizes the role it may play in the future of research and development.
—Jonah
References
- Graph-powerd Machine Learning at Google. Google AI Blog. https://ai.googleblog.com/2016/10/graph-powered-machine-learning-at-google.html (Accessed Feb 28, 2019).
- Jurs, P.C.; Kowalski, B.R.; Isenhour, T.L. Computerized Learning Machines Applied to Chemical Problems: Molecular Formula Determination From Low Resolution Mass Spectrometry. Chem. 1967, 41, 21-27.
- Machine Learning, Materials Science and the New Imperial MOOC. Imperial College London. https://www.imperial.ac.uk/news/187054/machine-learning-materials-science-imperial-mooc/ (Accessed Feb 28, 2019).
- UBC Summons. University of British Columbia.
Monosodium Glutamate (MSG): What is it and how harmful is it really?
Most of us have probably come across the term MSG while eating at a restaurant or when using canned food, but what is it, and how harmful can it be?
Monosodium glutamate (MSG) is a crystalline powder that is widely used in the food industry as a flavour enhancer that intensifies the meaty/savoury flavour found in certain food items. It was discovered in 1908 by the Japanese chemistry professor Kikunae Ikeda, where he extracted MSG from seaweed. MSG is the sodium salt of glutamic acid (also known as glutamate), a non-essential amino acid that can be found in our bodies.
Photo source: BUSINESSINSIDER
MSG can either be synthesized or found in certain foods. These foods contain different amounts of glutamate. For example, Parmesan cheese, soy sauce, and fish sauce all contain more than 1000mg/100g of that food item. If you’ve ever wondered why these food items are so mouthwatering, this may be why!
Unfortunately, MSG is suspected of causing certain symptoms such as, headaches, heart palpitations, chest pain, nausea, and others. The substance first got its bad reputation when Robert Ho Man Kwok experienced abnormal heart rates, weakness, and numbness after eating excessive amounts of Chinese food. His colleague later decided that MSG was the cause of these symptoms without any scientific evidence. Further studies have since been done, for example, Ohguro et al. have done tests on rats before, the results showed damaged retina when 10 grams of sodium glutamate was added to a 100 gram diet. However, a simple search on the safety of ingesting MSG will result in find articles that state that there is no link between MSG and health hazards. Hence, the potential risks associated with MSG remain controversial. For now, MSG has been classified by the food and drug administration (FDA) as “generally recognized as safe.” This said, the FDA still requires manufacturers to label any food items that contain MSG.
To conclude, further studies need to be conducted to conclude whether MSG is a potential risk to one’s health. Although it may seem that there is a certain “catch” to flavour enhancers, our bodies can’t actually distinguish between naturally occurring glutamate and glutamate from MSG. As a matter of fact, today’s technology can’t differentiate between the two either. That being said, it is not a challenge to avoid food containing MSG for those that are concerned.
For more information on MSG, consider the following video:
Produced by the American Chemical Society
-Isabelle Lee
References
- Center for Food Safety and Applied Nutrition. Food Additives & Ingredients – Questions and Answers on Monosodium glutamate (MSG). .https://www.fda.gov/food/ingredientspackaginglabeling/foodadditivesingredients/ucm328728.htm (accessed Jan 27, 2019).
- Katherine Zeratsky, R. D. How does your body react to MSG? https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-answers/monosodium-glutamate/faq-20058196 (accessed Jan 27, 2019).
- Bright Tribe, I. Glutamate in Food – The Glutamate Association https://msgfacts.com/glutamate-in-food/ (accessed Jan 27, 2019).
- The Truth in Labeling Campaign is all about knowledge. https://www.truthinlabeling.org/ (accessed Feb 14, 2019).
