MINIATURE MICROWAVE POWERED STEAM STERILIZATION CHAMBER

A small device for the rapid ultrahigh temperature sterilization of su rfaces is described. Microwave power generated by a 2.45 GHz magnetron is delivered via coaxial cable to a silicon carbide block housed with in the chamber, Small quantities of water or aqueous hydrogen peroxide . are introduced into the chamber. Upon application of power, the liqu id flashes to vapor and superheats producing temperatures to 300 degre es C. The hot vapor permeates the enclosed space and contacts all expo sed surfaces. Complete microbial kill of > 10(6) colony forming units of the spore forming thermophile, Bacillus stearothermophilus, has bee n demonstrated using a variety of temperatures and exposure times in b oth steady state and thermal pulse modes of operation. (C) 1997 Americ an Institute of Physics.