Fluorescence of chromatin DNA by an oxazolium scintillator

Aqueous solutions of a yellow and highly fluorescent derivative from dimethyl-POPOP, obtained by treating a chloroform solution of this oxazole scintillator with dimethylsulfate, induce a strong blue-green or yellow-green fluorescence in chromatin DNA under ultraviolet (365 nm) or violet-blue (436 nm) excitation, respectively. It is suggested that this new and selective fluorescence reaction could originate from binding of the oxazolium derivative into the minor groove of DNA.