Why 70% IPA Is More Effective Than 100%

IPA or 2 propanol is widely used as a disinfectant in the pharmaceutical sector. It kills microorganisms such as bacteria, fungi, and viruses. All the equipment used in the pharmaceutical industry are finley disinfected with IPA, to ensure the removal of microorganisms. The concentration of IPA used, plays an important role in killing microorganisms.

IPA kills microbes by dissolving plasma membrane and destroying proteins.

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.

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.

How to prepare 9 liters of 72% IPA 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

1 ml = 72/100
For 9 liters or 9000 ml

72/100×9000=6480ml or 6.48Liters

Or simply calculate the 72% of 9 liters as follow,

72/100× 9= 6.48 Liters.

Calculate water as follow

It is clear from the above statement that if 72% is IPA then the remaining 28% should be water.So calculate 28% water same as above,
and answer is as following,
28/100×9=2.52 Liters

To prepare 9 liters of 72% IPA solution we have to mix 6.48 liters of IPA and 2.52 liters of water.