COVID-19 in 2019,as profoundly changed the world, and people are paying more attention to a safe and healthy way of life,such as taking personal protection when going out, washing hands frequently, and wearing masks.

Hydroalcoholic hand sanitizing gelswith ethanol, water and carbomer can effectively inhibit and remove hand bacteria without resistance because it does not need to be rinsed with water.At the same time, you can wash your hands freely at anytime and anywhere and take care of your health conveniently. Therefore, it is increasingly favored by people.

Hydroalcoholic hand sanitizing gels have can be formulated to provide pleasant sensory and good conditioning on the hands even while providing effective disinfecting performance. NM-Carbomers as rheology modifiers are the preferred polymers to provide cost-effective and aesthetically pleasing ingredients to thicken and stabilize hydroalcoholic gels.

Hydroalcoholic gels basically contain four major ingredients: alcohol, water, rheology modifier carbomer and neutralizer. The effectiveness of the sanitizer using alcohol depends on the amount and type of alcohol.

The FDA proposed monograph considers the effective concentrations as follows:

• Ethanol at 60-95 v/v%

• Isopropanol at 70-91.3 v/v%.

Alcohol can destroy the lipid containing cell membrane of bacteria and fungus and denatures proteins and enzymes inside bacteria and fungus. Alcohol kills bacteria and fungus almost instantly upon contact.

Carbomers Selection

Although all NM-Carbomers can thicken hydroalcoholic systems, Traditional carbomer such as NM-Carbomer 940HC, carbomer 980H are cost efficient. But Improved carbomers such as NM-Carbomer 1342, NM-Carbomer 1382/Carbopol 1382, with inci name Acrylates/C10-30 Alkyl Acrylate Cross polymer behave better with higher clarity, viscosity. NM-Carbomer 20， carbomer 2020，carbomer 21，carbomer 10, carbomer 30  offer advantages such as higher clarity, better efficiency, ease of handling and better overall aesthetics for hand sanitizing gels.

 A typical hand sanitizing gel contains less than 40 wt.% deionized waters. Due to this constraint, the processing ease, makes NM-Carbomer 20/21/10/2020 /30 well-suited for these types of formulations as compared to the more traditional NM-Carbomer 940 HC/980HC being cost efficient. The following table will assist in carbomer selection.

Procedure:

 1.Disperse NM-carbomer polymer by sprinkling on the surface of deionized water. Mixing at high speed.

 2. Slowly add ethanol with high mixing. Allow as much air to escape as possible before proceeding.

 3. Add the TEA with gentle sweeping motion to minimize air entrapment. Mix until uniform.