Platinum-pyrimidine complexes for electron microscopic cytochemistry of deoxyribonucleic acid

Platinum-pyrimidine complexes that are amorphous and highly soluble in water when used as sole electron-dense stains show high selectivity for nucleic acid-rich areas like chromatin, nucleolus and ribosomes. A method is presented for the selective staining of deoxyribonucleic acid. Glutaraldehyde-fixed tissue are exposed to 3 N HCL hydrolysis for an optimum time of 1 hr at room temperature before being embedded in Epon. Thin sections are then exposed to Schiff's reagent for 30 min and treated with 1% platinum-pyrimidine complex. The results inselective staining of structures containing deoxyribonucleic acid.