FLUORESCENT BRIGHTENERS - NOVEL STAINS FOR THE FLOW CYTOMETRIC ANALYSIS OF MICROORGANISMS

Flow cytometry is a rapid method for measuring the optical properties of individual cells. The technique has found great utility in the stud y of mammalian cells, but microbiological applications have been more limited. We here show that UV-excited fluorescent whitening agents, in particular Tinopal CBS-X, are effective stains for both vegetative mi crobial cells and for spores of Gram-positive bacteria. Pretreatment o f samples with ethanol speeds the staining process. Under favourable c onditions, Tinopal CBS-X may be used to discriminate among organisms, a fact that may be useful when screening for a target microorganism ag ainst a high biological background. (C) 1997 Wiley-Liss, Inc.