Fluorescence Analysis as a Tool for Determination of Viability of Microorganisms

Abstract

Fluorescence analysis brings a new insight into cell viability assay, which is based on selective staining of cell attributes and functions. A wide variety of fluorescent probes are now available. The most frequently employed methods for detection of the viability are markers of membrane integrity, intracellular esterase activity, the existence of transmembrane potential, respiration activity and maintenance of intracellular pH. Although in many microbial strains the use of a single fluorescent probe is sufficient for determination of whether the cell is dead or alive, a combination of two or more stains is recommended for better understanding of cell physiology and its changes. An increasing number of publications indicate that the fluorescence staining together with flow cytometry, which enables rapid and precise analysis of thousands of cells within seconds, can serve as a powerful tool for the determination of the microbial culture viability and heterogeneity.