An evaluation of possible intracellular nucleic acid quenching of carcinogenic hydrocarbon fluorescence

An investigation was made to evaluate the role of intranuclear nucleic acids on the reported lack of accumulation of fluorescent, polycyclic, carcinogenic hydrocarbons (CH) within the nucleus of the live cell. Analysis of CH distribution with integrated phase‐contrast and u‐v‐fluorescent microscopy was performed on whole cells and subcellular nuclear fractions from which nucleic acids had been removed and on ultracentrifuged live cells whose nuclei were stratified into nucleic acid‐rich and nucleic acid‐poor regions. No intranuclear fluorescence was found in any experimentally‐treated material or in the live cell controls after their exposure to CH. The absence of any evidence for the quenching of CH fluorescence by intranuclear nucleic acids supports the u‐v‐fluorescence microscopists' contention that little or no CH enters live cell nuclei.