Properties of SZTS (4-Acetoamido-4′-Isothio-Cyanostilbene-2,2′-Disulfonic Acid): Fluorescence and Biological Staining

Abstract

The emission spectra of the fluorochrome, SITS, are stable in the pH range of 4.5—12.0. The wavelength range giving maximum excitation was 340-360 mμ; range of maximum emission, 415-420 mμ In the animal cell types tested, HeLa, Chang liver, mouse L, and monkey kidney, all cellular membranes stained, but cell walk of plant tissue (Allium cepa) did not. The staining solution was 5 mg/ml of SITS in Earle's balanced salt solution. The preparations were mounted and viewed microscopically in this solution or, after staining and protracted storage in 9:1 methanol-formalin mixture they were mounted and viewed in this fixative. SITS may be useful as a vital dye since it distinguishes between living and dead cells.