HKUST−1 loaded Ag/TiO2 nanoparticles/graphene oxide composites modified sensor for sensitive detection of nicotine in electronic cigarette liquids

Electronic cigarettes (e-cigarette) have become more and more popular among young smokers in recent years. Nicotine, the main addictive component in cigarettes, is widely present in many e-cigarette. Assessing levels of nicotine is critical to the health of consumers and the development of tobacco industry. Herein, a novel electrochemical sensor based on Ag/TiO2 nanoparticles, metal–organic frameworks (MOFs) and graphene oxide (dual−NPs@HKUST−1/GO) nanocomposite was prepared for the rapid detection of nicotine in e-cigarette. The composites were characterized by scanning electron microscopy, X-ray diffraction, Raman spectroscopy and Fourier transform infrared spectroscopy, respectively. The results showed that the successfully synthesized composites have an average size of (20 ± 5) μm and excellent characterization properties. Under optimized conditions, the peak current response of nicotine with the differential pulse voltammetry showed a linear relationship in the range of 0.025–300 μM with a detection limit of 0.0145 μM. This newly developed dual−NPs@HKUST−1/GO-based sensor exhibited excellent selectivity, sensitivity and reproducibility for the accurate detection of nicotine. In addition, it also has excellent performance in detecting nicotine in actual e-cigarette refill liquids. The recoveries ranged from 88.6 % to 101.8 % in e-cigarette refill liquids, indicating good detection performance. This method provides a new concept for the detection of nicotine in the tobacco industry and clinical fields.