DETERMINATION OF DNA USING SODIUM 9,10-ANTHRAQUINONE-2-SULFONATE AS AN IN-SITU PHOTOCHEMICAL FLUORESCENCE PROBE

An in situ photochemical fluorescence probe method for the determinati on of DNA with sodium 9,10-anthraquinone-2-sulfonate (AQS) as a photoc hemical fluorescence probe was developed. It was based on the conversi on of AQS into an intensively fluorescent product by irradiating with UV radiation. The photochemical reaction is retarded by DNA. The deter mination can be carried out by measuring the fluorescence intensity at a fixed time. The calibration graph was linear in the range 0-80 ng m l(-1) calf thymus (CT) DNA (r = 0.9991), the limit of detection was 3. 2 ng ml(-1) CT DNA (n = 9). The kinetic behaviour of the photochemical reaction and the effects of experimental conditions were investigated and discussed in detail. The results of absorption spectra and compet itive binding experiments suggested the interaction between AQS and DN A to be intercalative.