Alcohol-based Hand Sanitizers and Their Demand

May 22, 2020

You may be thinking, where has all the hand sanitizers gone? Before the pandemic occurred the world merely produce under 3 billion litres of hand sanitizers per year but now the World Health Organization (WHO) expects that healthcare professionals will need 35 billion liters per year. This shortage will last longer than expected.

The Covid-19 pandemic has led to many companies starting to produce hand sanitizers to deal with the shortage. The common active ingredients that are used to formulate alcohol-based hand sanitizers are Ethanol and Isopropyl Alcohol.

Isopropyl Alcohol

Isopropyl Alcohol, also known as 2-propranol, is an isomer of propyl alcohol. As it has antibacterial properties, it usually functions as a disinfectant in many products. Besides rubbing alcohol, they are found in lotions, alcohol swabs and alcohol pads that can be used to disinfect minor cuts and wounds.

Ethanol vs Isopropyl Alcohol

Ethanol remains the most commonly used active ingredient in alcohol-based hand sanitizers but the high demand has resulted in people looking around for alternatives. You may wonder if isopropyl alcohol is equally effective or is it harmful to the skin? Let us provide you with a comparison so that you can understand which active ingredient to select.

	Ethanol	Isopropyl Alcohol
Mechanism	Denaturing proteins and lipids Both are effective against lipid-wrapped viruses e.g. coronavirus
NEA Minimum Recommended Dosage	70%	50%
CDC Minimum Recommended Dosage	60%	60%
Skin Hydration	More drying	Less drying
Maha Chemicals’ Recommended Dosage	75%	75%

Skin Hydration Results – Patch Tests

Figure 1 Löffler, H., Kampf, G., Schmermund, D. and Maibach, H. (2007), How irritant is alcohol?. British Journal of Dermatology, 157: 74-81. doi:10.1111/j.1365-2133.2007.07944.x

The results indicated that isopropyl alcohol (2-propanol) is less drying to the skin compared to ethanol. Furthermore, dehydration is less pronounced at higher alcohol concentrations. However, too high alcohol concentrations in a hand sanitizer may reduce its effectiveness. This is because proteins are not easily denatured in the absence of water.

The highest antimicrobial efficacy can be achieved with ethanol (60% to 85%), isopropanol (60% to 80%). Therefore, Maha will recommend that the dosage of ethanol and isopropyl alcohol to be 75% in your hand sanitizer formulation.

Formulation Guide : Hand Sanitizer

Phase	Material	INCI Name	Supplier	% W/W
A	Ethanol (95%) or Isopropyl Alcohol	Ethanol (95%) or Isopropyl Alcohol	–	75
	Deionized Water	Deionized Water	–	30.54
	Aloe Vera Extract	Aloe Barbadensis Leaf Extract	TEN	2
	SuperGel™ CE	Carbomer	Sino Lion	0.6
B	AMP-ULTRA PC 2000	2-amino-2-methyl-1-propanol	ANGUS	0.36
C	Sinopol 25	Polysorbate 20	Sino Japan	1.2
D	Fragrance	Fragrance	–	0.3

Procedures

Disperse Carbomer into phase A and stir to mix well
Neutralize with phase B under agitation
Add Phase C under agitation
Add phase D under agitation, and then obtain the product.

End Product Appearance

Appearance	Clear Gel
pH	6.0-6.5
Viscosity, cps	13000~18000Pa.s (25℃, Brookfield RVT, 20rpm, 6#spindle)