Aza-BODIPY Dye as Near Infrared Fluorescent Marker for Tagging Petroleum Products

Abstract

A new near-infrared fluorescent compound based on Aza-BODIPY derivative was designed and successfully synthesized as a taxation petroleum marker. The fluorescence emission of the new marker in the near-infrared region could help eliminating the interference of other compositions in the petroleum products, and the marker could be simply quantified by fluorescence spectroscopy. This new Aza-BODIPY marker was also functionalized by long-chain hydrocarbon via amide formation, therefore, its solubility in petroleum products was superior than the available commercial makers. Consequently, the new Aza-BODIPY marker was highly soluble in different fuel oils including diesel and gasohol. The fluorescence emission of the marker was in NIR frequencies which helped avoiding the interferences of petroleum products, which included diesel, gasohol 91, and gasohol 95, even at low concentrations of the marker at 1, 2, 4, 6, 8, and 10 ppm. Moreover, this fluorescent petroleum marker was not only stable under storage for at least 3 months but the marker also did not affect the physical properties of the fuel oils at a concentration of 2 ppm according to the American Society for Testing and Materials standard (ASTM).