Hematoxylin staining in quantitative DNA cytometry: an image analysis study

The suitability of commercial and pure aluminum-hematein for quantitative DNA image cytometry was investigated. Cervical smears, breast cancer aspiration biopsies, and rabbit liver tissue imprints were stained with Mayer's and Harris' al-hematein with variable staining times and dye concentrations. Pure and commercial hematoxylin was used. Nucleic acids were removed by enzyme digestion or by HCl-hydrolysis. A standard Feulgen stain served as control. DNA-polyacrylamide films were used as staining models. Absorption was measured using a VIDAS image analyzer. DNA in liver cell nuclei was not stained in a stoichiometric dye-DNA ratio. Sequential staining of cervical smears with hematein followed by the Feulgen reaction gave a covariance between 0.77 and 0.88 for IOD. Photometric errors due to unspecific RNA or protein staining were remarkable. Harris' and Mayer's hematein gave comparable results. Pure hematein gave slightly better results than commercial batches. DNA staining in model films was not quantitative with hematein. Al-hematein should therefore not be used for quantitative DNA cytometry.