UV-Vis spectrophotometric determination of isoprene in atmosphere based on Diels-Alder reaction

Isoprene is the most abundant biogenic volatile organic compound in the atmosphere. Till now, chromatography is the main detection method for isoprene, dependent on sophisticated instruments and complex operations. An UV-Vis spectrophotometric method based on the Diels-Alder (D-A) reaction was developed to detect isoprene in the atmosphere. The fast D-A reaction between the probe 4-phenyl-1,2,4-triazolin-3,5-dione (PTAD) and isoprene may cause absorbance decrease, which enable it to detect isoprene in solution at 118 nmol center dot L-1 level. Further, isoprene in air at the level of ppbv was detected using this method. Compared with chromatography this method has the advantages of low cost, fast and less dependence on instrument.