Alcohol disinfectant
The most commonly used alcohol disinfectants are ethanol and isopropyl alcohol, which can coagulate proteins and cause the death of microorganisms. It is a medium-effective disinfectant that can kill bacterial reproduction and damage most lipophilic viruses, such as herpes simplex. Viruses, hepatitis B virus, human immunodeficiency virus, etc.
The microbicidal effect of alcohol will be affected by organic matter, and because it is volatile, soaking disinfection or repeated scrubbing should be used to ensure its action time. Alcohols are often used as solvents for some disinfectants and have a synergistic effect. The common concentration is 75%. According to foreign reports: 80% ethanol has an excellent inactivation effect on viruses. In recent years, there have been many compound alcohol disinfectants at home and abroad, and these products are mostly used for hand skin disinfection.
Physical and chemical properties
Alcohol is also ethanol (C2H5OH). The concentration of medical ethanol is not less than 94.58%W/ml. It is a colorless and transparent liquid that is volatile, spicy and flammable. Its boiling point is 78.5°C and its flash point is 9- 11°C, can be mixed with water in any proportion.
Denatured alcohol contains toxic substances added to ethanol, such as methanol, formaldehyde, mercury chloride, etc. It is not drinkable, but it can be used for disinfection and has the same effect as ethanol.
Isopropyl alcohol (CH3CH(OH)CH3), also known as 2-propanol or dipropanol, is a colorless, volatile liquid and is an isomer of n-propanol CH3-CH3-CH2-CH2OH. The concentration is not less than 98.5%. It is a colorless and transparent flammable liquid with an odor similar to that of acetone and ethanol. It tastes slightly bitter and has a boiling point of 82.5°C and a flash point of 11.7°C. It can be mixed with water and ethanol.
How to use
75% ethanol solution is used for soaking, scrubbing and disinfection, mainly for hand skin disinfection.
70% isopropyl alcohol solution is used for soaking, scrubbing and disinfection.
Disinfection mechanism
Alcohol disinfectants rely on three functions to kill microorganisms:
① Damage protein skin and denature it;
② Invade human bacterial cells and detach the water film on the surface of the protein, causing it to lose activity and causing microbial metabolism disorders;
③Bacteriolysis.
Bactericidal effect
Ethanol has a killing effect on bacterial reproduction, viruses and fungal spores. Gram-positive bacteria are slightly more resistant than Gram-negative bacteria and are ineffective against bacterial spores.
60%-70% ethanol can kill bacterial reproduction (including Mycobacterium tuberculosis) for 5 minutes; for viruses, because they are mostly wrapped in proteins, it takes a long time (3-10 minutes), and for hepatitis B The effect on viruses is still controversial; on fungal spores, it takes 30 minutes. When the ethanol concentration is lower than 30%, the killing of bacterial reproduction also needs to be extended to several hours.
Isopropyl alcohol can kill bacterial reproduction, some viruses and fungal spores, but cannot kill bacterial spores.
Alcohol Poisoning Treatment
Those with oral poisoning should induce vomiting immediately and repeat gastric lavage with 1% sodium bicarbonate or water. 60~100ml of 50% glucose, intravenous injection, and 16~20 units of insulin, subcutaneous injection, and intramuscular injection of vitamins B1, B6 and niacin to promote ethanol oxidation and wake up. Symptomatic and supportive treatment, pay attention to keeping warm, use naloxone for those who faint, 0.4~0.8mg each time, can be used repeatedly, use sedatives with caution. Maintain electrolyte balance and acid-base balance.
Hemodialysis is suitable for patients with extremely high blood ethanol concentration in severe poisoning (ethanol concentration >110mmol/L or 500mg/dl).
Disinfection efficacy
Alcohol and isopropyl alcohol are both commonly used medium-efficiency disinfectants. The difference in disinfection effect is not very big. If you really need to compare, isopropyl alcohol has a better disinfection effect than alcohol because the official ingredient of isopropyl alcohol is Dimethylmethanol contains two groups of methyl groups, which greatly enhances its lipophilicity, and is an outstanding hydrophilic and lipophilic amphoteric alcohol. Because of its strong penetrability, its ability to kill bacteria and mold is also enhanced accordingly. Alcohol generally refers to a 75% ethanol medical water solution, which contains a group of ethyl groups. The penetrating power of ethyl groups is weaker than that of methyl groups, which further widens the functional gap between the two. The ingredients of many medical disinfection tablets on the market are actually Composed of 70% isopropyl alcohol and non-woven fabric.