November 15, 2012
Condoms have a 15 percent failure rate. Also, they do not completely protect against sexually transmitted diseases (STDs). However, when researchers at the University of Manitoba soaked condoms in a solution of microscopic silver nanoparticles, the condoms seemed to kill all HIV and herpes viruses in lab experiments.
Silver has been known to have disinfectant powers, but its effectiveness was not reliable. According to Dr. Xiaojian Yao, lead author of the study, when silver was used in a nanoparticle form, it seemed to become more effective at fighting off bacteria and viruses. The small size of the nanoparticles also enabled the researchers to place them on a polyurethane condom without changing its size or shape. The researchers do not know exactly how the silver nanoparticles neutralize HIV and other viruses.
Dr. Yao added that the silver nanoparticles do not cause inflammation. Currently, there are condoms treated with the antimicrobial called Nonoxynol-9, but these can cause inflammation and genital ulcers, which may make infection more likely. Also Dr. Yao noted that the treated condoms are quickly discarded, so that the potentially toxic metal does not remain in users' bodies. Another consideration is that discarded nanosilver-treated condoms could prevent infecting anyone who finds and touches them.