Please note that soap is an anionic surfactant, which means it has a negative charge, which means it can create micelles, that will literally rip the coronavirus' membrane apart. Soap molecules are easily drawn into the lipid bilayer of a cell membrane.
The combination of citric acid plus sodium bicarbonate also creates an anionic surfactant with a negative charge.
From Google:
1 Answer
Carbon dioxide, water, and sodium citrate solution
Explanation:
Alka Seltzer is a mixture of sodium bicarbonate, citric acid, and acetyl salicylic acid. The sodium bicarbonate and citric acid are there mainly to create a pleasant tasting fizzy antacid solution. The acetyl salicylic acid is "aspirin", the active ingredient which is a pain killer, and this will only be present in small quantity probably around 250 mg per tablet.
When water is added, the sodium bicarbonate and citric acid are dissolved, forming aqueous ions which react to yield carbon dioxide, water, and the sodium salt of citric acid (sodium citrate). The pH of the final solution is sufficiently basic to act as a remedy for acid stomach and the aspirin simply dissolves in the water, so it can be consumed more easily so that it can fight headaches or similar types of pain.
The reaction is:
Citric acid (aq) + Sodium bicarbonate (aq) -> Carbon dioxide + water + Sodium citrate
Outside the Box
The coronavirus is no match for plain, old soap — here’s the science behind it
Soap works better than alcohol and disinfectants at destroying the structure of viruses
This is how soap removes dirt, and bacteria, from the skin.
PALLI THORDARSONWhy does soap work so well on the new coronavirus and, indeed, most viruses? Because it is a self-assembled nanoparticle in which the weakest link is the lipid (fatty) bilayer.
That sounds scientific. Let me explain.
Soap dissolves the fat membrane, and the virus falls apart like a house of cards and “dies,” or rather, it becomes inactive as viruses aren’t really alive. Viruses can be active outside the body for hours, even days.
Disinfectants, or liquids, wipes, gels and creams containing alcohol (and soap) have a similar effect but are not as good as regular soap. Apart from alcohol and soap, antibacterial agents in those products don’t affect the virus structure much. Consequently, many antibacterial products are basically just an expensive version of soap in how they act on viruses. Soap is the best, but alcohol wipes are good when soap is not practical or handy, for example in office reception areas.
Soap outcompetes the interactions between the virus and the skin surface, and the virus gets detached and falls apart like a house of cards.
Supramolecular chemistry
But why, exactly, is soap so good? To explain that, I will take you through a journey of supramolecular chemistry, nanoscience and virology. I will try to explain this in generic terms, which means leaving out special chemistry terms. (I must point out that, while I am an expert in supramolecular chemistry and the assembly of nanoparticles, I am not a virologist.)
I have always been fascinated by viruses, as I see them as one of them most spectacular examples of how supramolecular chemistry and nanoscience converge.
Most viruses consist of three key building blocks: RNA, proteins and lipids.The RNA is the viral genetic material — it is similar to DNA. The proteins have several roles, including breaking into the target cell, assisting with virus replication and basically being a key building block (like a brick in a house) in the virus structure.
The lipids then form a coat around the virus, both for protection and to assist with its spread and cellular invasion. The RNA, proteins and lipids self-assemble to form the virus. Critically, there are no strong “covalent” bonds holding these units together.
Instead, the viral self-assembly is based on weak “non-covalent” interactions between the proteins, RNA and lipids. Together, these act together like Velcro, so it is hard to break up the self-assembled viral particle. Still, we can do it — with soap!
Most viruses, including the coronavirus, are between 50-200 nanometers — so they truly are nanoparticles. Nanoparticles have complex interactions with surfaces they are on; it’s the same with viruses. Skin, steel, timber, fabric, paint and porcelain are very different surfaces.
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When a virus invades a cell, the RNA “hijacks” the cellular machinery like a computer virus and forces the cell to make fresh copies of its own RNA and the various proteins that make up the virus.
These new RNA and protein molecules self-assemble with lipids (readily present in the cell) to form new copies of the virus. That is, the virus does not photocopy itself; it makes copies of the building blocks, which then self-assemble into new viruses.
All those new viruses eventually overwhelm the cell, and it dies or explodes, releasing viruses that then go on to infect more cells. In the lungs, viruses end up in the airways and mucous membranes.
When you cough, or especially when you sneeze, tiny droplets from the airways can fly up to 30 feet. The larger ones are thought to be main coronavirus carriers, and they can go at least 7 feet. So, cover your coughs and sneezes!
Skin is an ideal surface for viruses
These tiny droplets end up on surfaces and dry out quickly. But the viruses are still active. What happens next is all about supramolecular chemistry and how self-assembled nanoparticles (like the viruses) interact with their environment.
Now it is time to introduce a powerful supramolecular chemistry concept that effectively says: Similar molecules appear to interact more strongly with each other than dissimilar ones. Wood, fabric and skin interact fairly strongly with viruses.
Contrast this with steel, porcelain and at least some plastics, such as Teflon. The surface structure also matters. The flatter the surface, the less the virus will “stick” to the surface. Rougher surfaces can actually pull the virus apart.
So why are surfaces different? The virus is held together by a combination of hydrogen bonds (like those in water) and hydrophilic, or “fat-like,” interactions. The surface of fibers or wood, for instance, can form a lot of hydrogen bonds with the virus.
In contrast, steel, porcelain or Teflon do not form much of a hydrogen bond with the virus. So the virus is not strongly bound to those surfaces and is quite stable.
For how long does the virus stay active? It depends. The novel coronavirus is thought to stay active on favorable surfaces for hours, possibly a day. What makes the virus less stable? Moisture (“dissolves”), sunlight (UV light) and heat (molecular motions).
The skin is an ideal surface for a virus. It is organic, of course, and the proteins and fatty acids in the dead cells on the surface interact with the virus through both hydrogen bonds and the “fat-like” hydrophilic interactions.
So when you touch a steel surface with a virus particle on it, it will stick to your skin and, hence, get transferred on to your hands. But you are not (yet) infected. If you touch your face, though, the virus can get transferred.
And now the virus is dangerously close to the airways and the mucus-type membranes in and around your mouth and eyes. So the virus can get in and — voila! — you are infected. That is, unless your immune system kills the virus.
If the virus is on your hands, you can pass it on by shaking someone’s else hand. Kisses, well, that’s pretty obvious. It goes without saying that if someone sneezes in your face, you’re stuck.
So how often do you touch your face? It turns out most people touch the face once every two to five minutes. So you’re at high risk once the virus gets on your hands, unless you wash off the active virus.
So let’s try washing it off with plain water. It might just work. But water “only” competes with the strong “glue-like” interactions between the skin and virus via hydrogen bonds. The virus is sticky and may not budge. Water isn’t enough.
Soap dissolves a virus’ structure
Soapy water is totally different. Soap contains fat-like substances known as amphiphiles, some structurally similar to the lipids in the virus membrane. The soap molecules “compete” with the lipids in the virus membrane. That is more or less how soap also removes normal dirt of the skin (see graphic at the top of this article).
The soap molecules also compete with a lot other non-covalent bonds that help the proteins, RNA and the lipids to stick together. The soap is effectively “dissolving” the glue that holds the virus together. Add to that all the water.
The soap also outcompetes the interactions between the virus and the skin surface. Soon the virus gets detached and falls apart like a house of cards due to the combined action of the soap and water. Boom, the virus is gone!
The skin is rough and wrinkly, which is why you need a fair amount of rubbing and soaking to ensure the soap reaches every nook and cranny on the skin surface that could be hiding active viruses.
Alcohol-based products include all “disinfectants” and “antibacterial” products that contain a high share of alcohol solution, typically 60%-80% ethanol, sometimes with a bit of isopropanol, water and a bit of soap.
Ethanol and other types of alcohol do not only readily form hydrogen bonds with the virus material but, as a solvent, are more lipophilic than water. Hence, alcohol does dissolve the lipid membrane and disrupt other supramolecular interactions in the virus.
However, you need a fairly high concentration (maybe 60%-plus) of the alcohol to get a rapid dissolution of the virus. Vodka or whiskey (usually 40% ethanol) won’t dissolve the virus as quickly. Overall, alcohol is not as good as soap at this task.
Nearly all antibacterial products contain alcohol and some soap, and that does help kill viruses. But some also include “active” bacterial killing agents, such as triclosan. Those, however, do basically nothing to the virus.
Alcohol works — to a degree
To sum up, viruses are almost like grease-nanoparticles. They can stay active for many hours on surfaces and then get picked up by touch. Then they get to our face and infect us because most of us touch our face frequently.
Water is not effective alone in washing the virus off our hands. Alcohol-based products work better. But nothing beats soap — the virus detaches from the skin and falls apart readily in soapy water.
Supramolecular chemistry and nanoscience tell us not only a lot about how the virus self-assembles into a functional, active menace, but also how we can beat viruses with something as simple as soap.
Palli Thordarson is a professor at the School of Chemistry at the University of New South Wales, Sydney. Follow him on Twitter and Facebook.
https://www.x-mol.com/paper/826259?recommendPaper=5670453
Comprehensive Study of the Self-Assembly of Phospholipid Nanodiscs: What Determines Their Shape and Stoichiometry?
Langmuir ( IF 3.557 ) Pub Date : 2018-09-21 00:00:00 , DOI: 10.1021/acs.langmuir.8b01503
Nicholas Skar-Gislinge, Nicolai Tidem Johansen, Rasmus Høiberg-Nielsen, Lise Arleth
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https://pubs.rsc.org/en/content/articlelanding/2020/sm/d0sm00336k#!divAbstract
Nanodisc self-assembly is thermodynamically reversible and controllable
*abc Abstract
Many highly ordered complex systems form by the spontaneous self-assembly of simpler subunits. An important biophysical tool that relies on self-assembly is the Nanodisc system, which finds extensive use as native-like environments for studying membrane proteins. Nanodiscs are self-assembled from detergent-solubilized mixtures of phospholipids and engineered helical proteins called membrane scaffold proteins (MSPs). Detergent removal results in the formation of nanoscale bilayers stabilized by two MSP “belts.” Despite their numerous applications in biology, and contributions from many laboratories world-wide, little is known about the self-assembly process such as when the bilayer forms or when the MSP associates with lipids. We use fluorescence and optical spectroscopy to probe self-assembly at various equilibria defined by the detergent concentration. We show that the bilayer begins forming below the critical micellar concentration of the detergent (10 mM), and the association of MSP and lipids begins at lower detergent levels, showing a dependence on the concentrations of MSP and lipids. Following the dissolution process by adding detergent to purified Nanodiscs demonstrates that the self-assembly is reversible. Our data demonstrate that Nanodisc self-assembly is experimentally accessible, and that controlling the detergent concentration allows exquisite control over the self-assembly reaction. This improved understanding of self-assembly could lead to better functional incorporation of hitherto intractable membrane target proteins.
https://healthmatters.nyp.org/how-does-handwashing-with-soap-kill-the-coronavirus/
How Soap Suds Kill the Coronavirus
A closer look at how washing your hands with soap and water for 20 seconds kills this lethal virus.
The new coronavirus has proven deadly, but it can also be defeated with something as simple as soap suds. In this animation, Health Matters explains how handwashing with soap kills the coronavirus and why it’s the best defense against the spread of COVID-19.
“Soap molecules disrupt the fatty layer or coat surrounding the virus, ” says Dr. David Goldberg, an internist and infectious disease specialist at NewYork-Presbyterian Medical Group Westchester and an assistant professor of medicine at Columbia University Vagelos College of Physicians and Surgeons. “Once the viral coat is broken down, the virus is no longer able to function.”
The best way to protect yourself from the coronavirus remains avoiding exposure — and helping to prevent its spread. That’s why the Centers for Disease Control and Prevention encourages social distancing, wearing a face mask in public places, and, of course, handwashing with soap. “Contaminated hands are one of the most important means of spread,” says Dr. Goldberg. “If you get the virus on your hands and touch your face, you can become infected. Also, if you touch someone else or some object which is then touched by someone else, the hands of that person can become contaminated, leading to further spread.”
In addition to soap and water, there’s one more thing to consider: time. That’s why the 20 seconds of handwashing with soap is so important. You work up a good lather, allowing the soap to do its magic. “The soap molecules need some time to react with the viral coat and break it up,” says Dr. Goldberg. “The process is reasonably fast, but it’s not instantaneous.”
To understand the science behind how handwashing with soap kills coronavirus, read the explanation in the animation:
You’ve probably heard that protecting yourself from COVID-19 means washing your hands for two rounds of the happy birthday song or 20 seconds of another favorite tune.
It may seem pretty mundane and simple, but a deep handwash is incredibly lethal to viruses. So why is soap such an effective killer against the novel coronavirus?
Let’s take a closer look at that dollop of soap in your hand. A soap molecule consists of a “head” that is hydrophilic — attracted to water — and a long hydrocarbon “tail” made of hydrogen and carbon atoms that is hydrophobic — or repelled by water.
When soap molecules dissolve in water, they arrange themselves into micelles, which are spherical clusters of soap molecules with the water-attracting heads on the outside and water-repelling tails on the inside.
The coronavirus has a core of genetic material surrounded by an outer sheath that’s a double layer of fats with protein spikes. This fatty sheath is water-repelling and protects the virus.
Let’s see what happens when we start washing our hands.
Back to the micelles: With a formation of water-attracting heads on the outside, and water-repelling tails on the inside that can dissolve fats, micelles become a lethal bundle of cells in water.
When they encounter coronaviruses, the water-repelling tails are attracted to the fatty envelope around the virus and insert themselves into the protective layer.
The virus shatters and is doomed down the drain.
But this doesn’t happen immediately. You need to take time to generate a good lather and cover all parts of your hands. That takes about 20 seconds.
And that’s why washing your hands is so effective in slowing the spread of the coronavirus.
Each time you create suds, you’re unleashing molecular assassins to attack and kill coronaviruses and, for that matter, nearly all other pathogens.
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