CONTROL OF MOS BY CHEMICAL AGENTS CONTD..

B) ALCOHOLS :
                       Alcohols are effective skin aspetics & valuable disinfectant for medical treatment. For practical, the preferred alcohol is ethanol & iso-propyl alcohol .Ethyl alcohol is generally used in the concentration of 70% . It is active against vegetative bacterial cells including Tubercule bacillus but has no effect on spores. Ethanol is a strong dehydrating agent. Methanol is poisonous & less bactericidal than ethyl alcohol. Higher alcohol like propyl & others are more germicidal than ethanol & germicidal power increases with increase in molecular weight.
             Ethanol & isopropanol  are often used to enhance the effectiveness of other chemical agents. For eg; an aqueous solution of Zephiran kills about 40% of the population of test organism in 2 minutes, whereas a tincture of Zephiran kills about 85% in same period.

USES: Alcohols are used in reducing microbial flora of skin,disinfection of thermometers, preservation of cosmetics, to treat skin before vein puncture or injection.

MODE OF ACTION:  The antimicrobial activity of alcohol is due to its property like protein denaturants, solvents for liquid, dehydrating agents. To know in detail about the mode of action of ethanol please visit this link below;
    http://en.wikipedia.org/wiki/Ethanol.                
http://wiki.answers.com/Q/Mechanism_of_action_of_alcohol_in_killing_bacteria.
http://jac.oxfordjournals.org/content/49/4/597.full.


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