A fluorescent molecular sensor based on ESIPT process for rapid detection of arsenic species in hydrophobic system

An excited-state intramolecular proton transfer (ESIPT)-based fluorescent sensor (M-HBT) was designed and synthesized and used to detect arsenic species in real naphtha sample. The pH-related emission movement from 610 nm (pH = 1) to 510 nm (pH = 13) evidenced the ESIPT process of M-HBT. The sensing property of M-HBT was investigated in ethanol, and the experimental results provided good linear response of As3+ in the region of 0–32 μM. A skin contact experiment of M-HBT detecting As3+ was designed by using the pork sample as a mimic. The naked-eye recognizing emission change of M-HBT was rapidly from yellow to green in 15 s. The fluorescent sensor M-HBT showed the better selectivity towards As3+ than other cations. The sensing mechanism of M-HBT to As3+ was verified by 1H NMR titration spectra.