ROOM-TEMPERATURE PHOSPHORESCENT PALLADIUM-PORPHINE PROBE FOR DNA DETERMINATION

Room-temperature phosphorescence (RTP) enhancement of a palladium-porp hine complex by DNA was studied, Studies involving calf thymus DNA and calf liver RNA revealed that the Pd-porphine complex bound to double- stranded DNA displayed intense RIP, while a very weak RTP emission was observed in the presence of equal molar concentrations of RNA. This f act founded a basis for selective determination of DNA in the presence of RNA. Maximum phosphorescence was observed at pH 7, with maximum ex citation and emission wavelengths at 435 and 680 mn, respectively. Und er optimal experimental conditions, the calibration graphs were linear up to 6 x 10(-5) mu M DNA. The detection limit was 5 x 10(-8) mu M an d the relative standard deviation (10 replicates) +/-2.6% in the linea r range. DNA extracted from human colon tissues could be successfully determined.