Sensing Legionella by Photogate-type Fluorescence Sensor

－Application to Legionella dumoffii－

Abstract

This work describes the way of sensing bacteria, Legionella by photogate-type fluorescence sensor. Photoirradiation time dependences of L. dumoffii with the UV-photointensity as a parameter was obtained by the optical sensor. The photocurrents obtained by the sensor decreased depending on the irradiation time, showing the decay process of fluorescent material in Legionella cells. Initial decay rates were also found to vary with UV-photointensity. These results indicate that the photogate-type optical sensor is able to detect Legionella by using a simple combination of photochemical reaction rate constant and the excitation light intensity.