Chemist reveals how to make your own hand sanitiser
Supermarkets and chemists around Australia are struggling to keep up with the demand for hand sanitiser and wipes as fear over the global coronavirus pandemic take hold
As shelves are stripped and strict buying limits enforced, people have turned to the internet in droves in search of recipes to create their own product. But experts have warned none are effective unless made using the correct ratios.
Sydney chemist Michelle Wong said while there are endless sites offering DIY recipes, the reality is making your own product "is not quite as easy as it sounds".
"A commercial product is much more reliable," Ms Wong said, "it is very easy to mess up a DIY recipe."
"Some of these DIY recipes aren't even going to work, even if you make them perfectly. If you use a hand sanitiser that you think is working, even though it isn't, then you are putting yourself at risk."
Recipes for at-home products given the tick of approval by Ms Wong are those posted online by the World Health Organisation (WHO).
One formula posted by WHO calls for 96 per cent-proof ethanol (8333ml), hydrogen peroxide 3 per cent (417ml) and 98 per cent glycerol (145ml). (It is worth noting the formula is for creating a 10 litre batch.)
Ms Wong said any recipe for a DIY product requires three essential ingredients with the most important of these being a high concentration of alcohol.
"You need a high alcohol concentration of between 60 to 95 per cent to reliably destroy viruses. This concentration is high enough to break down the envelope around the coronavirus and to denature the proteins inside it, so it can't infect you," Ms Wong said on a clip posted to her YouTube channel.
The other two ingredients are glycerol and hydrogen peroxide.
Glycerol, more commonly known as glycerine in beauty products, is a "humectant moisturiser".
This means it will help keep your hands moisturised because alcohol can dry out your skin.
"Other moisturising ingredients will also work for this, but it is best to use something water-based," Ms Wong said. "Alcohol-based sanitisers don't work that well on greasy hands."
The third element is hydrogen peroxide, which is included at a low concentration.
"This is there to kill any remaining bacterial spores in your ingredients on your equipment. It is not actually there to help actively kill any germs on your hand."
On the issue of natural products, Ms Wong warned those containing essential oils are unlikely to be effective "even if the person selling these to you is telling you otherwise".
"Even if an essential oil has been found to be effective against one type of virus, it doesn't necessarily mean it is going to be effective against this brand new coronavirus," she said.
Regardless of the method, Professor Peter Collignon, an infectious disease expert said there is no benefit to making a DIY hand sanitiser if they don't have correct alcohol to gel carrier ratios.
Speaking previously to news.com.au, Prof Collignon said: "The basic formula is two parts isopropyl alcohol to one part gel (aloe vera).
"Using alcohol which hasn't been diluted won't be effective."
Ethanol (ethyl alcohol), the alcohol found in distilled beverages, can also be used when making an at-home hand sanitiser mix.
As a disinfectant, ethanol is considered to be more effective against some types of infectious diseases than isopropyl alcohol.
It is worth noting, if substituting ethyl or drinking alcohol to ensure the spirit is 180 proof or higher.