By developing a method to chlorinate silk, U.S. Air Force researchers have found a route to the production of fabrics that kill bacterial spores and cells within minutes of exposure.
The latest episode in the American Chemical Society’s (ACS’) Global Challenges/Chemistry Solutions
podcast series describes a simple, inexpensive dip-and-dry treatment
can convert ordinary silk into a fabric that kills disease-causing
bacteria—even the armor-coated spores of microbes like anthrax—in
new “killer silk” has many potential uses, including make-shift
curtains and other protective coatings that protect homes and other
buildings in the event of a terrorist attack with anthrax.
Based on an article by Rajesh R. Naik, Ph.D., and colleagues in the journal ACS Applied Materials & Interfaces, the new podcast is available without charge at iTunes and from www.acs.org/globalchallenges.
Naik points out in the podcast that in adverse conditions, bacteria of the Bacillus
species, which includes anthrax, become dormant spores, enclosing
themselves in a tough coating. These spores can survive heat, radiation,
antibiotics and harsh environmental conditions, and some have sprung
back to life after 250 million years. Certain chemicals—most popular
among which are oxidizing agents, including some chlorine compounds—can
destroy bacterial spores, and they have been applied to fabrics like
cotton, polyester, nylon and Kevlar. These treated fabrics are effective
against many bacteria, but less so against spores. The researchers
tried a similar coating on silk to see if it could perform better
against these hardy microbes.
developed a chlorinated form of silk, which involves soaking silk in a
solution that includes a substance similar to household bleach and
letting it dry. Silk treated for just an hour killed essentially all of
the E. coli
bacteria tested on it within 10 minutes and did similarly well against
spores of a close anthrax relative used as a stand-in. “Given the potent
bactericidal and sporicidal activity of the chlorinated silk fabrics
prepared in this study, silk-Cl materials may find use in a variety of
applications,” the authors say. Other applications, they add, include
purifying water in humanitarian relief efforts and in filters or to
mitigate the effects of toxic substances.
Source: American Chemical Society