Determination of DNA by use of in situ photochemical fluorescence probe sodium 9,10-anthraquinone-2-sulfonate as a photochemical fluorescence probe

An in situ photochemical fluorescence probe method for the determination of DNA with sodium 9,10-anthraquinone-2-sulfonate(AQS) as a photochemical fluorescence probe was developed for the first time. It was based on the conversion of AQS into an intensively fluorescent product on irradiating with UV radiation. The photochemical reaction is decelerated by DNA. The determination can be carried out by measuring the fluorescence intensity at a fixed time. The calibration graph was linear in the range 0 ∼ 80 ng/mL CT DNA(r = 0. 999 1), the limit of detection was 3. 2 ng/mL CT DNA(n = 9). The kinetic behaviour of the photochemical reaction and the effects of some experiment conditions were investigated and discussed in detail. The results of absorption spectra experiments and competitive binding experiments suggest that the interaction between AQS and DNA may be intercalative.