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TechnoratiSilver as an antibacterial... why?
Submitted by Anonymous on 19 January 2006 - 2:07am.
I've become aware recently that silver is an increasingly popular antibacterial/antimicrobial. (Actually, my interest was sparked because I was given a pair of silver-infused ski socks, that apparently will prevent odor with fewer washings... hmm...) I have poked around the web looking for an explanation of this, and while I can find extensive information about its uses and new product developments and regulations, etc., I have found almost nothing regarding why silver kills bacteria.
So, here's my question: regarding its chemistry and basic biology, why does silver kill bacteria? Any help is GREATLY appreciated!!
Thanks again!
Its actually Nano-Silver
Its actually Nano-Silver used as an antimicrobial. That is silver that has been reduced to particles measured in billionths of a metre. This silver works as a catalyst for oxidation reactions. Disulfide bonds play an important role as reversible switches for proteins in bacteria. Silver works by denaturatiing the sulfide bonds in these proteins ( as a catalyst). Silver also acts in generating oxygen from air or water which in turn destroys the cell wall membranes of bacteria. Silver will only act in single cell species such as bacteria. Because it acts as a catalyst - it only "switches" a reaction on and therefore does not poluute the environment in any way. Its a good use of nanotechnology.
I found this link that
I found this link that explains the history and working of silver. I work for a spa and pool company and silver is a very popular santizer because it's so gentle and easy yet effective.
ok, i know im a bit late on
ok, i know im a bit late on this specific post, seeing that the last was in 2006. I do still hope someone humors me on my question, though.
Ok! here it goes... if Ag catalyzes the formation of O-radicals for oxidation doesn't that mean we shouldn't be exposed to it constantly? so if we use nano Ag tech on our food and laundy isn't this going to be a health problem too?
and with regards to silver particles attracting lead, i've been told that this also works in the body, right? some alternative med people use silver to detox the body of Pb... is this true or have i been misinformed
and lastly, will silverwear and silver pitchers also attract Pb? if so what happens when it accumulates on the surface of these items? can u wash it off with a strong household acidulant?
I would really appreciate the help! Thanks a lot!
-Misguided
It's either gonna be because:
(i) it just has plain nasty chemical properties which rip organic molecules to shreds (e.g. like chlorine in swimming pools and drinking water)
or (ii) cos it has subtle properties which allow it to get inside their cells and mess with their biochemistry, by fooling them that it's something they want, and only far far too late to they realise their hideous mistake MWOAH HAH HAH
I'm guessing it's (ii), cos silver is a gentle soul, really?
But I do not actually know :)
But as good chemists, we should be able to have a good guess just from our knowledge of the periodic table:
what sort of solubility does silver have?
what sort of ions does form?
what does it like to bond with?
Nano silver works only on
Nano silver works only on single cell bacteria. It works in 2 ways. Either denaturation or oxidation - and possibly both. Its action is as a catalyst only. The denaturation mechanism is where disulfide bonds in an importnat protein( enzyme) are cleaved or disconnected. This prevents the bacteria from exerting any control on exposure to oxidation reactions. Nano silver will also generate reactive oxygen in either air or water which effects the cell wall of bacteria in much the same way any strong base,such as Hydrogen peroxide, will kill bacteria. Nano silver does all this whilst acting only as a catalyst for the reaction. Thus it is long lasting and perfectly safe.
However odour in clothes are caused by far more complex mechanisms than single celled bacteria. Bacteria may form microscopic slime which is then food for other higher order micro species and then the formation of breakdown chemicals that really cause the odours. Bacterial slimes are usally exopolysaccharides which are very tough. Silver will have zero effect on bacterial slime. Only good old fashioned washing with detergent will work.,
Can you list any academic websites that say this is true?
I think perhaps it is just the interpretation of some of the properties of silver that are being mis interpreted here.
On my England Football (Soccer to you Mitch) shirt I had a tag outlining the wonders of the X-static fibre technology, on eof the points was:
"The anti-microbial properties of silver inhibit the growth of bacteria in the X-STATIC® fabric"
http://www.noblefiber.com/ for more stuff from that material.
I recon it's just that bacteria and stuff just don't grow on very clean surfaces....and silver tends to be rather clean, doe it not?
Ag and Cu are definitely toxic to bacteria; CuSO4 is added to kill cyanobacteria in water supplies (and my tenth-grade biology teacher used copper nails to kill his neighbor's ricepaper tree which was damaging his driveway); Ag is used in silver sulfadiazine (1% in cream) which is the way in which burns are treated to prevent infection and scarring; I would suspect that both interfere somehow with the cellulose membrane which is a feature shared by plants, bacteria, and fungi)
I just checked John Emsley's Building Blocks, which states "the silver ion Ag+ is deadly to both bacteria and viruses" It also mentioned that AgNO3 is regularly given as eyedrops to newborns to prevent blindness cause by bacteria infections. Emsley goes on to say that therapeutic use of silver was formerly limited by the incredible ability of Cl- to precipitate Ag+ and that an excess of Ag+ imparts a grey color to skin, hair and eyes (p. 393) Ah well ...
However, it seems that silver is so stable that it is impossible to form such compound or ions by just adding a silver layer on the product. Besides, if that's the case, the silver layer will be used up, right?