I have previously worked on the effect of gold nanaoparticles on food poisoning bacteria and it show great hindernce abilities also by transission electron microscope scanning the salmonella cell was badly affected and the flagella was destroyed comletely ..for more details please check my publicarion with refernce " Zawrah M. F. and Sherein I. Abd El-Moez (2011): Antimicrobial Activities of Gold Nanoparticles against Major Foodborne Pathogens. Life Science Journal, 8(4): 37-44."

I thinsk you can find relation ship between the gold and silver nanoparticles MOA

Thanks Sherein for your input. I've seen your paper, it is a good paper on experimental research. My question is more on the fundamental research. I like to know how these nano particles works in this bacteria killing process? Whether same nano particle can be used again and again? Whether the killing action will be same every time? I shall appreciate, if you can address my questions from your vast research experience. Thanks Manas

Hi manas, we have worked with silver nanoparticles in vitro and we saw that, against Salmonella, the action is time-dependent and, probably as you say, ions are neutralized (see publication in Losasso et al. Frontiers in Microbiology in my profile). The exact mechanism of action is not known, there is a ROS mediated activity and, according to some authors, also a direct effect of nanoparticles. Also in the case of fibers with nanoparticles the action is likely to be time limited.

I am wondering, where the silver nanoparticles are supposed to go or get transformed. After all it is an element which does not decay like say , radioactive elements.

Thanks Simone, I also feel that metal ion is neutralized after killing bacteria. If this is so, the antibacterial effect of silver induced materials reduce with uses. I've not seen any such research to support such hypothesis. Nano silver has antibacterial effect, but it is much less than that of silver ion.

That is the in built property of Silver to present Oligo dymanic action, inhibiting the growth of bacteria.

Thanks Rupal, but why silver is more active in ion form? I've seen some works have been done in Rice University on this, but still the mechanism is not very clear.If you know more about the mechanism, pl. share...Manas