by Jeffrey Gardner, Associate Professor of Biological Sciences, UMBC

Editor’s note: As concern about coronavirus grows, hand sanitizer is in high demand. Biologist Jeffrey Gardner explains why alcohol is a key ingredient in hand sanitizer, and why he doesn’t recommend making your own supply at home.

1. Why is alcohol the main ingredient in most hand sanitizers?

Alcohol is effective at killing different types of microbes, including both viruses and bacteria, because it unfolds and inactivates their proteins. This process, which is called denaturation, will cripple and often kill the microbe because its proteins will unfold and stick together. Heat can also denature some proteins – for example, when you cook an egg, the solidified egg whites are denatured proteins.

2. Alcohol doesn’t kill some microbes very well – why not?

There are different types of bacteria and viruses, and some types are more easily killed by alcohol. For example, E. coli bacteria, which can cause foodborne illness and other infections, are very effectively killed by alcohol at concentrations over 60%. Differences in the outside surface of various bacteria make alcohol sanitization more effective against some of them than others.

Similarly, some viruses have an outer wrapping, which is called an envelope, while others are non-enveloped. Alcohol is effective at killing enveloped viruses, including the coronavirus, but is less effective at killing non-enveloped viruses.

Whether you are trying to kill bacteria or viruses, many research studies have found that an alcohol concentration of 60% or greater is needed to be effective.

3. If 60% alcohol is good, is 100% better?

Surprisingly, no. Protein denaturation actually works faster when a small amount of water is mixed with the alcohol. And pure alcohol would evaporate too quickly to effectively kill bacteria or viruses on your skin, especially during winter when the air is less humid.

Using 100% alcohol also would dry your skin out very quickly and cause it to become irritated. That might cause you to not sanitize your hands as frequently as needed. This is why most hand sanitizers contain emollients, which are mixtures that help soften and moisturize your skin.

4. Are homemade hand sanitizers a good idea?

In my view, no. You may see do-it-yourself formulas online, including some that use vodka. However, vodka is typically 80 proof, which means it’s only 40% alcohol. That’s not high enough to effectively kill microbes.

The rubbing alcohol you have in your bathroom for cuts and scrapes might seem like a good alternative, but if you are already near a sink, the best choice is to wash your hands with soap and hot water.

5. Does hand sanitizer expire?

Most commercial hand sanitizers are effective for a couple of years when they are stored properly, and are marked with expiration dates. One thing to keep in mind is that alcohol is volatile, which means that over time the alcohol will slowly evaporate and the sanitizer will lose its ability to effectively kill viruses and bacteria. However, with hand sanitizer in such high demand now, you’re unlikely to buy one that is expired.

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[You’re smart and curious about the world. So are The Conversation’s authors and editors. You can get our highlights each weekend.]

Jeffrey Gardner, Associate Professor of Biological Sciences, University of Maryland, Baltimore County

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Header image: Soap and hot water is the best way to clean your hands, but sanitizer is a good second choice.
AP Photo/Ric Feld

Reminder: FORMS-F Grant Application Forms & Instructions Must be Used for Due Dates On or After May 25, 2020- New Grant Application Instructions Now Available

Notice Number: NOT-OD-20-077

https://grants.nih.gov/grants/guide/notice-files/NOT-OD-20-077.html

This notice reminds the NIH and AHRQ applicant and recipient community that applicants must use FORMS-F application packages for due dates on or after May 25, 2020 and must use FORMS-E application packages for due dates on or before May 24, 2020 (see NOT-OD-20-026 for details).

For a transition period, both FORMS-E and FORMS-F application packages and instructions will be active, simultaneously. 

Please refer to the full notice for details regarding implementation of FORMS-F.

By Adam Sachs, RD, Campus Dietitian

The COVID-19 (coronavirus) outbreak has dominated the news and seems to be on everyone’s mind. It is important to listen to facts and experts on this topic when looking for new and updated information. Food preparation and diet can be one of largest factors to staying healthy and preventing the spread of disease. Make sure to use caution and follow some of these guidelines to adjust your diet and food preparation techniques

When preparing any type of food WASH YOUR HANDS FIRST. Especially if you are preparing food for others. Avoid touching your mouth, eyes or nose when preparing food. Make sure to clean and sanitize your work space and use clean utensils and equipment. Be very aware of food expiration dates, and the status of fresh items in your fridge. If anything appears or smells spoiled, it is safest just to throw it away. Remember to clean as you go during meal prep. It is also a great practice to prepare meals in large batches. Portions of these meals can be frozen and saved for later dates.

If you are eating out or getting food from a restaurant try to get take-out or delivery if possible. Many restaurants may also be dealing with shortages for certain ingredients or be unable to store everything, so be prepared to be flexible with some of the menu items.

There are also some diet and lifestyle changes we can all make to ensure that our immune system is functioning a peak performance. Make sure to get plenty of fruits and vegetables. Fresh, frozen, and even canned can all be equally nutritious. Many fruits and veggies contain vitamins and minerals that help to boost our immune function. Citrus fruit, tropical fruit, and cruciferous vegetables contain lots of vitamin C, which supports healthy immune function. 

Also look for foods high in Zinc. Nuts/seeds, eggs, dairy, shellfish, and legumes are all a great source. Also make sure that you are consuming enough fluids. The average adults needs about 60-90oz of water per day, so try to meet that minimum if you can. Lastly, make sure you are getting an adequate amount of sleep. Sleeping fewer than 6 hours per night for three or more days has been show to suppress immune function. Taking regular naps, and avoiding screen time before bed can help to boost your sleep time and quality.