Automatic mapping of viable microbial cells distributed in the surface layer of cotton fabrics

Viable microbial cells distributed in a 130 microim thick surface layer of cotton fabrics were stained with a fluorescent glucose, 2- [N- (7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino] -2-deoxy-D-glucose (2-NBDG), and automatically mapped with an ultra-deep focusing range microscope (UDF) system. The software of the UDF system was upgraded and the number of Candida albicans cells could be counted at a higher precision than before. Bacterial cells of Pseudomonas fluorescens, Serratia marcescens, and Citrobacter freundii, which were smaller than 1-2 microm, were successfully mapped for the first time. These results indicate the practical importance of the present method in the evaluation of the antibacterial properties of fabrics and the efficacy of washing.