Purdue University Cytometry Laboratories in collaboration with Dr. Ernest Blatchley in the Department of Civil Engineering and Dr. Cindy Nakatsu in the Agronomy Department are currently working on developing rapid methods to investigate the effect of disinfectants (i.e. gamma irradiation, ozone, chlorination) on pathogenic microorganisms.

Recent outbreaks of pathogenic microorganisms in drinking water systems (i.e Cryptosporidium parvum, Giardia sp., E.coli) demonstrate the need for a rapid and reliable method to identify and characterize viable organisms in environmental samples.

The recent development of fluorochrome labeled rRNA-targeted probes combined with improvements in flow cytometric instrumentation offers an exciting opportunity to study mixed microbial communities in drinking water systems and to understand microbial responses to changing environmental conditions. These probes allow specific identification of targeted microorganisms, and more importantly can provide an indication of cell viability and community response to environmental stress.