Labeling procedures employing crystalline fluorescein isothiocyanate.

Griffin, Charles W. (Baltimore Biological Laboratory, Baltimore, Md.), Theodore R. Carski, and George S. Warner. Labeling procedures employing crystalline fluorescein isothiocyanate. J. Bacteriol. 82:534-537. 1961.-The effect of altering the ratio of dye to protein in the labeling of three immune globulins with crystalline fluorescein isothiocyanate was the purpose of the study. Direct staining of group A streptococci and rabies-infected mouse brain, and indirect staining of Treponema pallidum (Nichols strain) comprised the three immunological systems selected for investigation. Maximal specific staining and minimal nonspecific background staining were demonstrated by the use of low dye-to-protein labeling ratios.