Characterization of bacteria by mixed-dye fluorometry

Document Type


Publication Date



We describe an indirect detection method for bacterial identification and differentiation, based on selective adsorption of several fluorescent dyes. The lipid, protein, and nucleic acid components of fixed whole cells are stained with two mixtures, each containing two fluorochromes. The unadsorbed dyes were measured simultaneously with a video fluorometer. A dye-absorption matrix of the response can be generated, and we did so for each of nine bacteria. These responses were compared to a control or 'complete' response matrix, and the response ratios of each bacterial species for each of the four dyes were calculated and plotted to obtain a characteristic pattern. From the response-ratio plots, plus simple pattern-recognition techniques, we could differentiate among all the bacteria. This rapid, sensitive technique is potentially applicable to a wide variety of bacteria.

Publication Source (Journal or Book title)

Clinical Chemistry

First Page


Last Page


This document is currently not available here.