Alcohol can achieve the purpose of sterilization by denaturing protein in bacteria. Also known as ethanol, it is an organic compound with strong permeability, which enables it to penetrate the outer membrane of bacteria and penetrate into the interior of bacteria. Then alcohol reacts with protein, which constitutes the interior of bacteria, to coagulate protein and make it lose its biological activity, which in turn leads to the loss of biological activity of bacteria, thus achieving the purpose of sterilization.
In our life, the common alcoholic products are industrial alcohol, white wine and medical alcohol. Industrial alcohol cannot be used to disinfect wounds because it contains methanol as an impurity. This is because methanol can be absorbed into the human body by damaged skin and form formaldehyde under the action of liver organ dehydrogenase. The aqueous solution of formaldehyde is called formalin solution. Formaldehyde has a special selective destructive effect on optic nerve and central nervous system in human body, which can cause protein degeneration of these tissues, thus causing serious consequences such as eye discomfort, nausea and vomiting, systemic pain and even blindness. Moreover, formaldehyde may continue to react with dehydrogenase to produce formic acid, which may lead to abnormal liver and immune functions, damage the central nervous system and damage the genetic material in cells.
Liquor can be used for disinfection, but it can only be used without disinfectant. The alcohol content of liquor on the market is mostly below 65%. Although this wine product has certain bactericidal effect, it is difficult to achieve the ideal effect because of the low alcohol concentration, so it is not recommended to use white wine as a disinfectant. Through experiments and long-term clinical data verification, the alcohol content is 75%, and the sterilization effect is the best. Below this value, its germicidal efficacy decreases with the decrease of alcohol concentration. When the concentration is too high, alcohol will first deteriorate the surface of bacterial protein, making it impossible to enter the bacteria to achieve sterilization effect. The alcohol concentration of medical alcohol is controlled at 75%, which is a professional bactericidal drug.
Therefore, although alcohol has bactericidal effect, it does not mean that all products containing alcohol can be used to disinfect wounds. Other ingredients contained in these products may not only bring about differences in sterilization effect, but also further damage wounds.
This paper was scientifically proofread by Xiao Qi, an associate professor in the Department of Chemistry and Printing Materials of Beijing Institute of Printing.