Why 70% IPA Is More Effective Than 100%

60-90% IPA give good antimicrobial activity and the concentration below 50 % and above 90% is not effective in killing microorganisms.100 % IPA does not kill microbes instead it coagulates the outer proteins rapidly which prevents further penetration of IPA and protects the remaining proteins so microorganisms go into a dormant stage and are not killed.

Water is also required along with IPA to kill microorganisms. Water acts as a catalyst to destroy proteins and slow down the evaporation of IPA and increase penetration of IPA and kill microbes by increasing the contact time of IPA.10 to 40% water is used along with IPA to make 60%-90% IPA solution. The optimum concentration of IPA which is considered best disinfectant is 70%.

How to Prepare 70% IPA
To prepare 1 Liter 70% IPA solution 700ml IPA and 300ml water are mixed. Purified Water is used to prepare the IPA solution.

Explanation
As we know to prepare 1 liter of 70% IPA solution we require 700 ml of IPA and 300 ml water means 70% of our solution will contain IPA and 30% water.

Now we will learn how to calculate different concentrations of IPA solution.

Example
How to prepare 9 liters of 72% IPA Solution?

Solution
In the above statement it is clear that we have to prepare 9 liters of total solution and out of 9 liters 72% of total solution should be IPA and remaining water.

So calculate IPA as follow,

72% means

100ml contains 72 ml