FLUOROMETRIC-DETERMINATION OF THE DNA CONTENT OF CELLS CULTURED IN TISSUE-CULTURE PLATES

Determining the DNA content of cultured cells with the fluorochrome diaminobenzoic acid (DABA) has been shown to be a sensitive and selective method. A procedure is described which applies this method to cells cultured in 96-well and 24-well plates. After removal of the medium, the cells are disrupted by sonication, dried and reacted with DABA. For the final read-out the DABA-DNA solution is transferred to standard cuvettes and the fluorescence intensity determined with a conventional fluorometer. The method is highly reproducible and suitable for the cell concentrations usually employed in microculture systems. It is an easy non-radioactive method for determining the numbers of both adherent and non-adherent cells, especially when comparing different stages of activation or differentiation.