EVANESCENT FLUOROBIOSENSOR FOR THE DETECTION OF POLYAROMATIC HYDROCARBON BASED ON DNA INTERCALATION

A flow-injection analysis (FIA) system coupled with an evanescent wave (EW) biosensor employing total internal reflection of fluorescence ra diation (TIRF) for the detection of polyaromatic hydrocarbon that inte rcalates into DNA is reported. A highly fluorescent intercalator, ''et hidium bromide,'' has been used as the reference compound for detectio n. The EW biosensor was developed according to the procedure described earlier (1,2). Data on the analysis of Naphthalene, 3-methylcholanthr ene, 7,12-dimethylbenz(a)anthracene, 1,2-benzanthracene, and some stan dard reference materials supplied by the National Institute of Standar ds and Technology are reported. The relative ability of the polyaromat ic hydrocarbon to displace ethidium bromide, based on the relative bin ding ratio, is found to be on the order of 7,12-dimethylbenz[a]anthrac ene > 3-methylcholanthrene > 1,2-benzanthracene > napthalene.