How 70% alcohol works as disinfectant?
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Answer / senthilkumar
Alcohol is an antimicrobial compound killing the bacteria
by the process of dehydration and denaturation of
proteins.surface sterilization requires stability of such
agents on the surface for more time which is not found in
absolute alcohol(99%).So the absolute alcohol should be
diluted to 70% so that the evaporation of alcohol is
delayed.This ensures the proper sterilization of the surface
| Is This Answer Correct ? | 64 Yes | 7 No |
Answer / dinesh kumar , phd.
so many experiments have been done which confirm that at
100% or 99% the bacterial wall closed. so that water can
come outside from the bacterial wall. the pricciple for
alcohal sterilzation is dehydration of bacterial cells. but
at 100% concentration pore at the cell mambrane remain
closed. but at 75% pore remain open so that water can come
outside from the pores and bacteria can dehydarate. and
kill microbes.
this is the real answer of this question "why we use 75 %
alcohal not 100% or 99%.
ok so no confusn, just read some books.
| Is This Answer Correct ? | 31 Yes | 4 No |
Answer / rohan sharma
as an antiseptic, 70 percent of alcohol is prefered to a
stonger solution. Pure alcohol coagulates protein in
contact. Suppose the pure alcohol is poured ovr a single
celled organism. Th alcohol will penetrate the cell wall of
the organism in all direction, coagulating the protein just
inside the cell wall. the ring of the coagulated protein
would then prevent the alcohol from penetrating farther from
the cell, and no more coagulation woul take place. At this
time the cell would become dormant butnot dead. under the
proper condition the cell would then begin to function. if
70 percent of alcohol is poured to a single celled organism,
the diluted alcohol also coagulates the protein, but at a
slower rate, so that it penetrates all the way through the
cell before coagulation can block it. then all the cell is
coagulated and the organism dies.
Read more:
http://wiki.answers.com/Q/Why_is_70_percent_alcohol_a_better_disinfectant_than_100_percent_alcohol#ixzz1wyyIHrmO
| Is This Answer Correct ? | 22 Yes | 1 No |
Answer / himna
it is disinfectant b'coz it breaks the cell wall of
bacteria and denature it's proteins
| Is This Answer Correct ? | 26 Yes | 10 No |
Answer / yasodha
Bacterial cell wall breaks when exposed to 70 % alchohol
| Is This Answer Correct ? | 26 Yes | 18 No |
Answer / anil varghese p
Alcohol is an antimicrobial solution for killing the
bacteria and other insects
by the process of dehydration and denaturation of
proteins. Proteins will come outside from the bacteria due
to alcohol(70%). surface sterilization requires stability
of such
agents on the surface for more time which is not found in
absolute alcohol.So the absolute alcohol should be
diluted to 70% (the evaporation of alcohol is
delayed).This ensures the proper sterilization of the
surface
| Is This Answer Correct ? | 10 Yes | 8 No |
Answer / gazanfar abass
I believe their are various reasons that why 70% alcohol is more effective disinfectant than absolute alcohol. Out of all, the two important reasons are
1) Alcohol is an antimicrobial compound killing the bacteria
by the process of dehydration and denaturation of
proteins. Surface sterilization requires stability of such
agents on the surface for more time which is not found in
absolute alcohol(99%).So the absolute alcohol should be
diluted to 70% so that the evaporation of alcohol is
delayed.This ensures the proper sterilization of the surface
2)Pure alcohol coagulates protein in
contact. Suppose the pure alcohol is poured ovr a single
celled organism. Th alcohol will penetrate the cell wall of
the organism in all direction, coagulating the protein just
inside the cell wall. the ring of the coagulated protein
would then prevent the alcohol from penetrating farther from
the cell, and no more coagulation woul take place. At this
time the cell would become dormant butnot dead. under the
proper condition the cell would then begin to function. if
70 percent of alcohol is poured to a single celled organism,
the diluted alcohol also coagulates the protein, but at a
slower rate, so that it penetrates all the way through the
cell before coagulation can block it. then all the cell is
coagulated and the organism dies.
Further, as i said their many reasons, so any one knows any reasons other than the above two, i will be pleased if you forward that to me on my email ID that is gazanfar0966@gmail.com
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / anjali
as an antiseptic, 70 percent of alcohol is prefered to a stonger solution. Pure alcohol coagulates protein in contact. Suppose the pure alcohol is poured ovr a single celled organism. Th alcohol will penetrate the cell wall of the organism in all direction, coagulating the protein just inside the cell wall. the ring of the coagulated protein would then prevent the alcohol from penetrating farther from the cell, and no more coagulation woul take place. At this time the cell would become dormant butnot dead. under the proper condition the cell would then begin to function. if 70 percent of alcohol is poured to a single celled organism, the diluted alcohol also coagulates the protein, but at a slower rate, so that it penetrates all the way through the cell before coagulation can block it. then all the cell is coagulated and the organism dies.
| Is This Answer Correct ? | 2 Yes | 3 No |
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