Abstract
The bromination Feulgen variant (T. Barka: J. Histochem. Cytochem. 4: 208, 1956) can be used even in the Feulgen microspectrophotometry. The decrease in UV-absorption and gallocyanin-chromalum staining caused by brominatoin suggest that the bromination depolymerizes but one part of the ribonucleic acid, beside that it releases aldehyde groups in the deoxyribonucleic acid.