Treatment of chicken blood smears and semithin sections from Epon-embedded mouse tissues with aqueous solutions of the 3-aminonaphthalimides FA-142, FA-2043, and FA-2143 induced a strong green-yellow fluorescence of chromatin under violet or violet-blue excitation. Chromatin emission was abolished by previous DNase or hot TCA treatment. The use of 3-methoxy (FA-655) and 3-nitro derivatives (M-4...
