Killing bacteria the soft way: with chlorinated silk!


American and Indian scientists have developed a modified ordinary silk tissue that kills disease-causing bacteria in minutes, and even the armour-coated spores of microbes such as the highly dangerous anthrax! This research was in fact triggered by the search for a defense against bacterial warfare, used in the past by terrorists.

The “killer silk” is ordinary silk tissue, but simply treated with chlorinated compounds through a ‘dip-and-dye’ method. The researchers had a look at several oxidizing agents that could possibly be effective against bacteria and their spores. Among the tested agents were chlorinated substances. The active substances were applied to fabrics like cotton, polyester, nylon and the super-strong fiber Kevlar. All these treated fabrics were effective against bacteria, but less against their spores. It than showed that a chlorinated form of silk, dipped in a bleach-like solution and dried afterwards, was very effective. Silk that had been treated for only one hour was able to kill all E-Coli bacteria in the lab tests as well as their spores within ten minutes.

The scientific team foresees many applications for the new silk-chlorine materials, including treated curtains that protect homes and other buildings in the event of a terrorist attack with anthrax. Other applications could be purifying water in humanitarian relief efforts (earth quake, flooded land etc.) and use in filters for mitigating the harmful effects of several toxic substances.