Sterilization of a Small Caliber Vascular Graft with a Polyexpoxy Compound

Abstract

Sterilization of tissue based medical devices via cold sterilization processes has been limited to formaldehyde, glutaraldehyde, and mixtures of the same with alcohols and surfactants. The authors report the sterilization of a small caliber vascular graft with a combination of diglycidyl ether and ethanol. The sterilant contains 1-4% diglycidyl ether and 10-20% ethanol as an aqueous solution. Sterilization is achieved after exposure of the graft to the sterilant solution for a period of 7 days at an elevated temperature (30 degrees - 40 degrees C). The biologic indicator selected for efficacy studies was Bacillus subtilis niger ATCC 9372 (endospores). The grafts were inoculated with a concentrated endospore suspension and immersed in the sterilant solution for increasing time periods. After extensive rinsing over membrane filters to remove any residual sterilant, the grafts and filters were cultured in tryptic soy broth. D10 values were calculated using a fraction-negative, most probable number technique. Additionally, many representative bacteria and fungi were tested and found to be susceptible to the new sterilant developed. The diglycidyl ether/alcohol sterilant developed was found to be efficacious for sterilization of the tissue based vascular grafts tested.