Monthly Archives: January 2020

Should you be worried?—An Outbreak of Novel Coronavirus!

Posted on January 28, 2020 by | Leave a comment

Since December 2019, an unexplained pneumonia epidemic has occurred in Wuhan City, Hubei Province, China. An investigation found that these were related to Wuhan’s “South China Seafood Market”. Wuhan organized a multi-disciplinary expert consultation survey and used laboratory testing to identify pneumonia in Wuhan as viral pneumonia. On January 8, 2020, a new coronavirus was initially identified as the pathogen of the epidemic.

The spread of the novel Coronavirus

The outbreak of this infectious disease was first occured in Wuhan in December, 2019 and then spreaded globally since the huge flow og people in Wuhan during lunar new year. According to the New York Times, there are more than 4,500 people in Asia infected the coronavirus as well as many other are suspected. At least 106 people have died as of Jan. 27, 20.Sources: National Health Commission of the People’s Republic of China; local governments. Note: Data as of 9 p.m E.T., Jan. 27

Evolutionary sources of coronavirus  and molecular pathways for infecting humans

To analyze the evolutionary source and possible natural host of the novel coronavirus, the researchers in this paper analyzed genetic evolution by comparing the novel coronavirus with collected large amount of coronavirus data. It was found that the novel coronavirus of Wuhan belongs to Betacoronavirus which is a RNA virus that parasitizes and infects higher animals (including humans). It is adjacent to the SARS virus and the SARS-like virus group in the position of the evolutionary tree. Interestingly, their evolutionarily common outgroup is an HKU9-1 coronavirus parasitic to Rousettus bats. Therefore, the common ancestor of Wuhan coronavirus and SARS or SARS-like coronavirus is a virus similar to HKU9-1. As the evolutionary neighbors and outgroups of Wuhan coronavirus have been found in various types of bats, it is speculated that the natural host of Wuhan coronavirus may also be bats and Wuhan coronavirus is likely to have unknown intermediate host vectors during the transmission from bat to human.

Phylogenetic tree (Source)

The authors used molecular computational simulation methods to perform structural docking studies on Wuhan coronavirus S-protein and human ACE2 protein, and found that although 4 of the 5 key amino acids that bind to ACE2 protein in Wuhan coronavirus S-protein have changed, the amino acids after the change have perfectly maintained the interaction between SARS virus S-protein and ACE2 protein. This result indicates that Wuhan coronavirus infects human respiratory epithelial cells through the molecular mechanism of S-protein interaction with human ACE2 protein, predicitng that Wuhan coronavirus has strong ability to infect humans.

Cα RMSD of 1.45 Å on the RBD domain compared to the SARS-CoV S-protein structure (Source)

Tips for prevention of coronavirus (source):

  • Wash your hands with soap for at least 20 seconds and avoid touching you mouth, nose and eyes with unwashed hands.
  • Keep a safe distance with people who are sick
  • Cover your cough or sneeze with tissue and throw the tissue in the trash
  • Clean frequently touched surfaces

-Xinyue Yang

Posted on Jan. 27th. 2020

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Posted in Biological Chemistry, Chemistry News, Popular Science

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Toxic Receipt – Another BPA Problem After Baby Bottles

Posted on January 27, 2020 by | Leave a comment

Remember BPA was banned for making baby bottles by the Canadian government in 2010 due to its hormone-disrupting? You may think the problem is solved but BPA is still sneaking into people’s bodies and harm people’s health through a thing we are using daily—receipt.

Source: http://k.sina.com.cn/

After almost every payment is made, whether needed or not, the receipt will be printed out. These receipts are usually made of Bisphenol A (BPA)-containing thermal paper, which is an ink-free choice for most of the banks, supermarket, pos machine, etc.  You may think that is not a problem since you will only touch it for a few seconds rather than use it for daily drinking.

However, researchers at the University of Missouri have shown that BPA found on the heat-sensitive paper used in shopping receipts can be absorbed through the skin, significantly raising BPA levels in the body.

What is BPA Exactly?

BPA is the initial of Bisphenol A, it is a chemical raw material that can be added to plastics to make them colorless, transparent, durable, lightweight and impact resistant. BPA was widely used in the manufacture of baby bottles, water bottles, sealants for dental fillings, eye lenses and hundreds of other commodities until banned in 2010.

BPA is an endocrine disruptor that can interfere with the body’s endocrine system by mimicking the effects of estrogen. When BPA shows hormone-like effects, the real hormones in the body may not work properly.

And what’s worse is….

BPA Absorption Increased Significantly After Using Hand Sanitizer 

One study showed that using hand sanitizer or other skincare products before handling receipts increases the absorption of BPA by up to 185 times, reaching levels that can lead to obesity, diabetes, coronary heart disease, infertility, and cancer.

The study mimics a common behavior seen in fast-food restaurants: wash your hands with hand sanitizer, hold the receipt for a while, and then eat with that hand.

By testing BPA on hands, they found that after using hand sanitizer, large amounts of BPA were transferred from heat-sensitive paper to hands in just a few seconds. BPA transfers hundreds of times faster than in dry hands.

Source: https://doi.org/10.1371/journal.pone.0110509.g002

This is because hand sanitizers and skincare products (such as soaps, sunscreens, lotions) contain “dermal osmotic enhancers” used to enhance the delivery of the active ingredients in the products. This enhanced effect leads to a rapid transfer of BPA through the skin.

BPA passed on to the hands is absorbed through the skin and under the tongue when eating, leading to higher levels of the chemical in the blood and urine.

Source: https://doi.org/10.1371/journal.pone.0110509.g002

So, next time, remember to dry your hands before touching the receipt and wash your hands afterward. Or simply tell the waiter that you don’t need the receipt.

—–Yicheng Zhu

 

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Posted in Biological Chemistry, Chemistry News, Uncategorized

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Effective Means of Diagnosing Alzheimer’s Disease

Posted on January 27, 2020 by | Leave a comment

Alzheimer’s disease is an incurable disorder and mainly affects people over the age of 65. It is a fatal disease that must be treated early and carefully. A new method to detect early signs of the disease is currently being investigated. Researchers at the University of Porto studied carbon nanomaterials and their biosensing applications to determine the biomarkers of Alzheimer’s disease.

A recent study in 2019 urged the importance of biomarkers for indication of Alzheimer’s disease. It is estimated that 5.5 million Americans suffer from Alzheimer’s disease without a cure, and is rapidly increasing. This does not mean nothing can be done to help treat the disease. To enhance treatment for this disease, early diagnosis is necessary and requires a method of indication. The study focused on biomarkers of pre-clinical stages of Alzheimer’s. Stage 1 includes increased amyloid burden, stage 2 includes neuronal injury and evidence of neurodegenerative change, and stage 3 includes subtle cognitive decline. Although the biomarkers developed can provide good results, various criteria must be met.

Biomarkers of Alzheimer’s Disease (Source: Laurent Hemoye)

Another study mentions the ability to produce biosensors from nanomaterials mainly because of their electrochemical activity and biocompatibility. Carbon nanotubes display exceptional electronic properties, due to its high surface-to-volume ratio, and is most commonly used for biosensing. Graphene is also common, and can be functionalized by various functional groups to improve selectivity to biomolecules.

Structure of Nanotubes (Source: Carneiro et al.)

A demand for more research on developing credible biomarkers for Alzheimer’s disease is crucial for early diagnosis, as more studies show biosensing as a challenge. This could potentially enhance the understanding of the disease and invent a cure.

-Wilson Wong

 

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Posted in Analytical Chemistry, Organic Chemistry

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Is Your Headache “Normal”?

Posted on January 27, 2020 by | Leave a comment

If you experience a sudden and severe headache, be careful! It could be an intracranial aneurysm. An intracranial aneurysm is the ballooning of a weakened blood vessel in the brain, which causes an intense headache upon rupturing. Around 3% of the population have unruptured aneurysms, which should be treated before they rupture. In 2011, Aoki’s group at Kyoto University suggested that nonsteroidal anti-inflammatory drugs (NSAIDs) may be an alternative to surgical repair, which is currently the only treatment for aneurysms.

Unruptured aneurysm (left) vs. Ruptured aneurysm (right)
(Credit: Mayo Clinic)

Mechanism of NSAIDs

Inflammation leads to the growth and rupture of intracranial aneurysms, but NSAIDs reduce inflammation by inhibiting the cyclooxygenase (COX) enzymes, specifically the COX-2 pathway. When this pathway is activated by inflammatory stimuli, the COX-2 enzyme converts arachidonic acid to prostaglandin, which then upregulates sequential reactions to promote inflammation, and enlarges intracranial aneurysms. Aoki’s team observed that NSAIDs decreased the formation of intracranial aneurysms in mice within the first six weeks.

Risks associated with NSAIDs and surgical repair

Although this treatment seems promising, long-term use of NSAIDs may lead to cardiovascular and gastrointestinal side effects. There are two surgical options to treating aneurysms: endovascular coiling and clipping. A major risk for coiling is that it may develop vasospasm, which occurs when the vessel constricts and leads to tissue death; whereas clipping increases the risk of infection and death, as it is an open surgery.

Two surgical procedures: Coiling an unruptured aneurysm (left) vs. Clipping a ruptured aneurysm (right)
(Created with Notability)

Both surgical and potential pharmacological treatments come with their risks, but hopefully our advancing knowledge will soon bring forth safer therapies.

 

Athena Wang

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Posted in Biological Chemistry

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Dayvigo, A Novel Approach to Insomnia Therapy

Posted on January 27, 2020 by | Leave a comment

Sleep is an inherently simple process that is often enjoyed, yet there is still a possibility that it can become so inexplicably difficult. For instance, consider insomnia, a condition where falling asleep can often become practically impossible. Even though many potential factors and causes can induce the disorder, the consequences tend to all be the same. However, with the FDA’s recent approval of a new drug called DAYVIGOTM, which contains the active ingredient lemborexant, improvement of the current insomnia treatment modalities is possible.

What causes insomnia?

To understand the causes of insomnia, it is necessary to first acknowledge that it is defined in terms of both a symptom and a disorder. Making the distinction is vital, as it can adjust our conceptualisation of it entirely. For instance, considering insomnia as a disorder, one of the causes is likely to be stress. On the other hand, if we choose to define insomnia as a symptom, pain or even sleep apnoea are both likely causes. Be that as it may, some of the major causes are listed as follows: stress, anxiety, depression, poor sleep hygiene, other health issues, stimulants and lack of exercise. Although we are developing a better understanding of the condition, it is beginning to affect more people. In fact, one study has even estimated that the prevalence of the symptoms alone is roughly 30%, hence the need for remedies such as DAYVIGOTM.

DAYVIGOTM and the role of Lemborexant

According to the label on the FDA website, the drug has been designed to treat adult patients that are having difficulties with inducing or maintaining sleep. It is worth mentioning though that the effects produced by this drug are attributed to lemborexant, which is an orexin receptor antagonist. The IUPAC name is (1R, 2S)-2-{[(2,4-dimethylpyrimidin-5-yl)oxy]methyl}-2-(3-fluorophenyl)-N-(5-fluoropyridin-2-yl) cyclopropanecarboxamide, and the molecular formula is C22H20F2N4O2. What is interesting about the drug’s structure is the presence of a 3-membered cyclopropane ring at the very centre.

Structure of lemborexant

Chem Spider ID:34500836, (accessed 03:33, Jan 28, 2020)

Certain pharmacological tests conducted with the compound illustrate the efficacy of the drug in the onset and sustenance of sleep. For instance, the molecule selectively binds to the orexin receptors, which are thought to be involved in sleep regulation. Essentially what the drug does is it binds to the receptors, preventing the “wake-promoting neuropeptides orexin A and orexin B” from interacting and therein suppressing the feeling of wakefulness.

The billion-dollar question

Is the drug worth it? A study conducted by the Tufts Center for the Study of Drug Development estimated the cost of producing novel compounds at $1.395 billion (2013 USD). Even without factoring in today’s inflationary pressures, that number is staggering. Furthermore, there are several drugs currently available to treat insomnia. However, it has been shown that DAYVIGOTM is one of the first FDA approved substance to report safety data for 12 months. Furthermore, the drug is rapidly absorbed, binds with a high affinity and is selective. Hence, in my opinion, the use of the drug is warranted.

-Akash Panjabi

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Posted in Biological Chemistry

Targeting Oxygen sensitive Hypoxia-inducible factors (HIF-1s) can help cure Anemia and Cancers

Posted on January 27, 2020 by | Leave a comment

The 2019 medicine Nobel Prize winner Dr. Gregg L. Semenza found out that cancers and Anemia can be cured by targeting the oxygen-regulated hypoxia-inducible factors (HIF-1s) in the cells.

What are HIF-1s and how are they related to oxygen? 

We all need Oxygen to be alive. At a cellular level, oxygen is essential to cell viability as it provides an energy source (ATP) for important cellular activities. In our body, only red blood cells that contain hemoglobin can deliver oxygen for all the other cells. During a shortage of oxygen, erythropoietin (EPO) increases the production of red blood cells. Hence, more red blood cells are available to bind and deliver oxygen from the lung to the other parts of the body. Besides, vascular endothelial growth factors (VEGFs) can stimulate the formation of blood vessels in response to the lack of oxygen. By forming more blood vessels, the body can ensure that oxygen can get to other cells in different parts of the body.

HIFs are the oxygen sensing knob in our bodies. Hypoxia-inducible factors (HIF-1s) are composed of two different subunits-one being an oxygen-regulated HIF alpha subunit and the other being an oxygen insensitive HIF beta subunit.

The alpha subunit of the HIFs can sense the oxygen concentration changes. When the oxygen level is low, the two HIF subunits join to assemble the dimeric HIF-1s. The HIF-1s can then bind to genes that express EPOs and VEGFs. As a result, more EPOs and VEGFs are available to deliver limited oxygen to cells in different parts of the body. Meanwhile, when the oxygen level is high, fewer HIF subunits form the dimeric HIF-1s. Thus, fewer HIF-1s can bind to EPOs and VEGFs genes, which further leads to less EPOs and VEGFs proteins being expressed.

How can the researchers target the HIF-1s to cure cancer and Anemia?

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Cancer is a group of diseases with abnormal cell growth. HIF-1s can be targeted to treat cancer because by inhibiting the dimeric HIF-1s, the cancer cells will have fewer EPOs and VEGFs. Therefore, the cancer cells will have much harder time oxygen and without enough oxygen, these cancer cells can die.

 “By adding a small molecule that inhibits HIF-1s, added on to the other cancer drugs that patients are receiving, will allow those other drugs to be more effective in fighting cancer,’’ said Dr. Semenza

“And as for Anemia, targeting the HIF-1s could show promising effect.”

 He added: “Anemia is associated with the lower-than-normal amount of red blood cells or hemoglobin. By taking a pill of a drug that increases HIF-1s activity and turns on EPO.”

The discovery of this oxygen-sensitive knob HIF-1s is a milestone in cancer and Anemia treatments. Cancers and Anemia perhaps are not that scary.

 

Journal Reference :

Gregg L. Semenza. Pharmacological targeting of hypoxia-inducible factors. Annual Review of Pharmacology and Toxicology, 2019; 59: 379-403 DOI: https://doi.org/10.1146/annurev-pharmtox-010818-021637

-Pricia Ouyang

Jan 27th, 2020

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Posted in Biological Chemistry, Organic Chemistry

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Gold Nanoparticle Catalysis Involving Hydrogen Ten Times Lighter Than Usual

Posted on January 27, 2020 by | Leave a comment

Researchers at the University of British Columbia have accomplished a highly complicated reaction involving the lightest hydrogen and nano-scale gold particles (AuNPs), which may lead future research into the bizarre realm of the muonium-AuNP system.

A Moun. Source: flickr

Muon, an approximately 200 times heavier-than-usual electron, along with another electron, makes up Muonium. Muonium is a hydrogen derivative withs only one-tenth of the normal hydrogen mass. This unusual species has a half-life of 2 μ-seconds, ceasing to exist in less than a blink of eyes, which made analysis extremely difficult. Many of its applications remain as mysteries.

Gold nanoparticles (AuNPs) are sols –––– very small solid particles –––– of gold immersed in a fluid. They exhibit extraordinary optical properties that make them suitable for cancer detection. AuNPs are also the best transporters for cancer drugs inside the human body due to their tiny size and non-toxic nature.

Gold Nanoparticles absorbing light at different wavelengths. Source: Sigma-aldrich

In Chemistry, AuNPs are great heterogeneous catalysts––––reaction accelerators that differ in phase from the reactants. For example, a metallic solid speeding up the reaction of two liquids is considered a heterogeneous catalyst. These solid catalysts all together account for 90% of the catalysts used worldwide.

However, the reaction of AuNPs requires particles to be isolated from each other. In previous studies, this was achieved by “capping” gold with “long tail” chemicals to prevent interactions. But these “tails” would ultimately change the reactivity of the AuNP.

Gold nanoparticle
Source: flickr

Study into Muonium and uncapped AuNP would allow closer examination into the catalyzing properties of these unnatural species, enabling not only a basis for quantum mechanical calculations but also further exploitation of their biomedical benefits.

Researchers under the Fleming and MacFarlane group was the first in history to conduct an experiment on the reaction of  Muonium and size-varying uncapped AuNP in a porous silica environment. In addition, they examined the catalyzing behavior of AuNP on muon’s reaction with surface-absorbed benzene, creating a benzene-radical.

Fleming and MacFarlane’s group successfully demonstrated the catalyzing effect of gold nanoparticles. They found that the binding energy of benzene was considerably weaker on the AuNPs than on bulk gold metal surfaces.

The results of this avant-garde reaction of Muonium coincided with many theoretical quantum calculations, bringing theoretical hypothesis into practicability. After successfully observing the reaction parameters of the Muonium and AuNP system, “Future studies of surface-absorbed reactants by the μSR technique described herein…are planned,” the authors Proposed.

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Embarassed of Asian Glow? Don’t Worry, The Future is Promising

Posted on January 26, 2020 by | Leave a comment

Ever find yourself beet red after having a small drink? You’re not alone. Over one-third of East Asians and eight percent of the world population experience this awkward phenomenon; however, a solution is in the works. Just last month, researchers from Weill Cornell Medical College have solved this problem in mice, using targeted gene therapy.

What does asian glow look like? A before and after comparison. (Credits: Wikimedia Commons)

The Dangers of Asian Glow

Despite the variety of memes and jokes poking lighthearted fun at this phenomenon, asian glow comes with much dire consequences than just flushing red. The red glow is related to a deficiency in the ALDH2 enzyme, a key component in detoxifying alcohol. When you drink alcohol, the body converts this substance into acetaldehyde. Normally, acetaldehyde is then converted to the safer acetate via ALDH2; however in individuals with asian glow, this enzyme does not function normally and acetaldehyde builds up to toxic quantities. Since acetaldehyde is a cancer-causing agent, its accumulation drastically increases the risk of developing esophageal cancer by six to ten folds.

Conversion of alcohol to acetate is stopped in people with asian glow. This leads to toxic buildup of acetaldehyde. (Created with Notability)

A Glowing Solution…

Matsumura’s team reasoned if a lack of ALDH2 enzyme was the problem, maybe they could simply add it back in.

“We hypothesized that a one-time administration of a […] virus […] expressing the human ALDH2 coding sequence […] would correct the deficiency”

They tested their idea on three strains of mice: mice expressing functional ALDH2, mice lacking any ALDH2, and mice expressing a non-functional version of ALDH2. The latter two simulated the asian flush syndrome seen in humans. After introducing the mice with the ALDH2 gene and feeding them alcohol, the researchers monitored acetaldehyde levels in the blood.

Their hard-work paid off! In the two strains initially deficient for ALDH2 function, acetaldehyde levels and abnormal behavior associated with alcohol consumption lowered to near-normal levels. Furthermore, they found that one dose was enough to confer persistent and long-term protection.

From Mice to Humans: A Complicated Decision

Matsumura’s team emphasize that apart from nutritional supplements, ALDH2 deficiency has no current therapies. Although making the jump from mice to humans will be challenging, they assure the concept of virus-mediated gene therapy presents as an effective therapy. The million-dollar question is whether the risks of the glow outweigh the benefits of reduced alcohol consumption seen in affected individuals. To this Matsumura’s team maintains:

“the overall burden […] on human health, particularly […] cancer, supports […] gene therapy.”

What do you think?

 

-Kenny Lin

 

 

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Posted in Biological Chemistry, Chemistry News

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A Bright and Sunny Future

Posted on January 25, 2020 by | Leave a comment

Climate change has been a hot topic throughout the latter half of the decade, and one of the questions is how do we create sustainable energy. This study published in October 2019 indicated that the solution may come from the development of Dye-Sensitized Solar Cells (DSSCs). DSSCs are efficient and with low manufacturing costs, they make the ideal source for sustainable energy. This research group highlights a strategy of controlled synthesis of hierarchical materials, thus providing new applications to the development of sustainable energy products.

A DSSC Retrieved from: engadget

DSSCs utilize sunlight as its source of energy, which is then converted into usuable energy. Within its compartments, it contains a light sensitizer which is connected to a semiconductor that faciliates the excitation of electrons which are able to enter a series of redox reactions. The continuous cycle of electrons through the circuit generates energy which can be used in our daily lives, or for other practical uses within industries. Huang et al., proposed to optimize the counter electrode (CE) that is present from a Pt CE, with a 2D nanosheet composed of Co-Ni-Se. This turned out to be successful as the Co-Ni-Se complex catalyzes the reduction of I3- electrolyte more effectively compared the traditional Pt CE that is typically used.

Schematic Diagram of a DSSC. Retrieved from: Research Gate Figure 2.

How can this be applied to us in everyday life?

Currently, greenhouse gases release CO2 into the atmosphere causing the earth to warm, and  subsequently acidifying the ocean affecting marine life as well. As a society, we must be more conscious of our carbon footprint as all our decisions have an environmental impact. DSSCs can be installed on the roofs of our houses to supply electricity during the day, instead of relying on sources like fossil fuels for energy. It can also be used to generate energy and stored within a battery pack for portable charging of cellular devices.

It is not difficult to find alternatives to our current problems to climate change, and one aspect more money should be invested in is the research and development of sustainable and renewable energy sources.

– Jackson Kuan

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Posted in Chemistry News, Inorganic Chemistry, Popular Science, Uncategorized

Breathe in the air… made from moon dust!

Posted on January 25, 2020 by | Leave a comment

On January 17th 2020, the materials and electrical components laboratory of the European Space Research and Technology Centre (ESTEC) in Noordwijk, Netherlands announced the launch of an oxygen plant: a facility designed to extract oxygen from moon dust. Using molten salt electrolysis, oxygen gas (O2) can be extracted from oxygen-rich compounds commonly found on the lunar surface. The ability to produce oxygen on the moon will benefit future lunar endeavors as oxygen is used for breathing and rocket fuel production.

Simulated moon dust before (left) and after (right) oxygen extraction by molten salt electrolysis. The byproducts (right) are metal alloys. (Credit: Beth Lomax, University of Glasgow)

Moon dust, formally known as moon regolith, is rich in metal oxides. Metal oxides contain metals with strong bonds to one or more oxygen atoms. These oxygen atoms require a significant amount of energy to liberate in order to produce oxygen gas. In molten salt electrolysis, simulated moon regolith is placed in a metal basket with calcium chloride (CaCl2) and heated to 950oC to melt the calcium chloride. An electric current is applied to the heated sample, producing oxygen gas and metal alloys.

The idea of making the most of lunar resources has been driven by space agencies’ (such as NASA and the European Space Agency) desire to start sending humans to the moon again, but this time with the intentions of staying and setting up a lunar base. The ability to self-sufficiently produce oxygen would be a vital asset to these missions, reducing the cost and urgency of supply missions to the moon. The metal alloy byproduct may also benefit lunar missions as ESTEC researchers now work on identifying the most useful components of the byproduct and their potential applications.

 

-Mark Rubinchik

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Posted in Chemistry News, Inorganic Chemistry

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