Surgical Instruments are sterilized by heating them and ALCOHOL is used as disinfectant in cleansing the skin prior to an injection. Why are these methods effective against microorganisms ?

Question

joppei · Answer

Because microorganisms that survive at about our body temperature (they have to be able to survive in our body to cause an infection, right?) Cannot withstand temperatures above the denaturation temperature of proteins which is mostly at about 45 degrees Celsius. But they sterilize it at +100 degrees Celsius because some bacteria also form spores that are very heat resistant.

The alcohol on the skin is supposed to be effective (it has been proven it has no effect) because it clears your skin of microorganisms that can otherwise enter your bloodstream along with the needle-injection or afterwards. Alcohol dissolves the cell membranes of the bacteria leaving them exposed to the surroundings and causing them to die with 99,9999 % significance