Inactivation of microbes using compressed carbon dioxide - an environmentally sound disinfection process for textiles

Abstract

High-pressure (HP) CO2 treatment was applied to disinfect a fabric which is frequently used in hospitals. The physical properties of the treated textile were evaluated and found not to be negatively influenced. Subsequently, the significance of the main parameters influencing the disinfection process were determined using multi-factor analysis of variance. Efficacy of the developed technique was demonstrated and optimised for Gramnegative Escherichia coli and Gram-positive Micrococcus luteus.Water addition was found to be crucial for the reduction of both bacteria species. Complete inactivation was achieved at temperatures as low as 20 ◦C for E. coli and 65 ◦C for M. luteus, respectively. The effective pressure required for the disinfection was only 50 bar. Finally, based on the experimentally revealed results, an empirical non-linear model was developed describing the inactivation of E. coli and M. luteus in the low-temperature process using highly compressed liquid, gaseous or supercritical CO2.