Hand Sanitizer : Introduction, composition, preparation and uses
Introduction of Hand Sanitizer
Hand sanitizer composition has alcohol that kills the microbes by two mechanisms i.e. protein denaturation and dissolving the lipid membrane. According to the WHO trusted Source, an alcohol-based hand sanitizer that meets the alcohol volume requirement can quickly reduce the number of microorganisms on your hands. It can also help destroy a wide range of disease-causing agents or pathogens on your hands, including the novel coronavirus which is now called COVID-19.
Composition of Hand Sanitizer
WHO based composition of hand sanitizer preparation
Hydrogen peroxide: 0.125%
For 250 ml
Ethanol (90%, V/V): 222.22 ml
Glycerol (98%, V/V): 3.63 ml
Hydrogen peroxide (6%, V/V): 5.21 ml
Distilled water (D/W): up to 25O ml
We can use simple V1S1=V2S2 formula.
Where V1 =volume of stock solution, S1= concentration of stock solution
V2=Volume of final solution and S2=Concentration of final solution
e.g. make 250 ml 80% ethanol from 90% stock
Micro pipette and tips
Procedure of Hand Sanitizer preparation
Pour 222.22 ml ethanol in a measuring cylinder or any graduated container.
Add glycerol 3.63 ml.
Similarly hydrogen peroxide 5.21 ml.
Put distilled water up to 250 ml marked label.
Mix properly and finally pour into appropriate container i.e. spray bottle as shown above image.
Use of hand sanitizer
Apply the sanitizer to the palm of one hand and thoroughly rub your hands together. Always mind you cover the entire surface of your hands and all your fingers. Rub your hands for 30 to 60 seconds or until your hands are dry. It can take at least 60 seconds, and sometimes longer, for hand sanitizer to kill most germs.
Glycerol is a very important ingredient because it prevents the alcohol from drying out your hands.
Your sanitizer composition must contain at least 60% alcohol to be effective.
Two things to be aware of when using hand sanitizer is that you need to rub it into your skin until your hands are dry. And, if your hands are greasy or dirty, you should wash them first with soap and water.
Improper ingredients or proportions can lead to lack of efficacy action towards microbes,skin irritation, injury, or burns.
If your hands look dirty or slimy, optional for hand washing instead of a hand sanitizer.
However, even the best alcohol-based hand sanitizers have limitations and do not eliminate all types of germs e.g. Norovirus, Cryptosporidium (parasite),and Clostridium difficile(bacteria).
Bailey and Scott’s Diagnostic Microbiology -13th Edn.
Mackie & Mc Cartney Practical Medical Microbiology- 14th Edn.