Facile Fabrication of a Functional Filter Tip for Highly Efficient Reduction of Nicotine Content in Mainstream Smoke

Development of amide-based molecular cages for the highly selective and sensitive detection of nicotine

Nicotine is a harmful sympathomimetic drug associated with serious health issues. Herein, a novel amide-based bistren-type cage, BiP-Am, has been developed for the selective fluorescence-based sensing of nicotine in human urine samples and cigarettes. The corresponding detection limit features a value of 0.4 nM, among the best reported in the literature. Selectivity experiments demonstrate that BiP-Am can efficiently detect nicotine in the presence of multiple interfering analytes such as sodium, potassium, urea and uric acid. A plausible mechanism has been proposed herein, revealing that nicotine is showing an inner-filter effect quenching the BiP-Am fluorescence emission. Our strategy poses a facile and versatile method for nicotine detection in portable applications.

A colorimetric sensor with dual-ratio and dual-mode for detection of nicotine in tobacco samples

Nicotine (NIC) is a harmful substance, drug, pesticide and chemical that is widely found in tobacco. It has carcinogenic, teratogenic and neurotoxic effects that have raised serious concerns. Herein, a colorimetric sensor with dual-ratio and dual-mode for the detection of NIC in tobacco samples was reported. The localized surface plasmon resonance signals of gold nanoparticles (AuNPs) and AuNPs-NIC are used as dual-ratio signals. The absorbance ratio of NIC to AuNPs or the absorbance ratio of NIC to AuNPs-NIC and the wavelength shift value of AuNPs-NIC are applied as dual-mode. Transmission electron microscopy, energy dispersive spectroscopy, dynamic light scattering spectroscopy, ultraviolet-visible spectrophotometry, cyclic voltammetry, and potentiostatic methods were used to characterize the sensor. Further analysis of NIC was conducted through morphological fitting and theoretical calculations. Under optimal conditions, the sensor shows a wide linear range of 5-500 μM. The detection limits for NIC are 2.48 μM, 1.63 μM and 1.34 μM, respectively. The experimental result shows that the dual-ratio signal of AuNPs and AuNPs-NIC has good selectivity and sensitivity, and can effectively reduce the interference of impurities on NIC detection. And the dual-mode of detection for NIC improves the accuracy and comparability of the result significantly. In addition, the proposed sensor was also applied to test NIC in tobacco samples with satisfactory recovery.

Insight into the effects of different oxygen heteroatoms on nicotine adsorption from cigarette mainstream smoke

Cigarette smoke contains many chemicals, including nicotine, which is harmful and can cause health problems such as carcinogenesis disease, cardiovascular, respiratory, renal, and reproductive systems. Removal of nicotine from mainstream smoke can be done through adsorption with filters or solid adsorbents. In this study, we explored the use of activated carbons for the removal of nicotine from cigarette mainstream smoke. Activated carbons were prepared from dried hemp (Cannabis sativa) stem at an activation temperature of 350-550 °C using phosphoric acid as an activating agent. The results showed that the activated carbons with variable surface functional groups and porosity exhibited high efficiency for nicotine adsorption, removing 68-88% of nicotine from cigarette mainstream smoke. Through X-ray photoelectron spectroscopy and temperature-programmed desorption analyses, we identified that oxygen-containing functional groups, particularly carboxylic groups, exhibited a superior ability to adsorb nicotine. The computational analysis with DFT simulations further supported the importance of oxygen-containing surface functional groups in facilitating nicotine adsorption, with the carboxylic group providing the lowest adsorption energy among other functional groups.

Ru(II)-modified metal organic framework as excellent electrochemiluminescence emitter for ultrasensitive nicotine detection

The sensitive and selective nicotine detection in cigarette is necessary due to the cigarette addiction problem and the neurotoxicity of nicotine on human body. In this study, a novel electrochemiluminescence (ECL) emitter with excellent performance was prepared for nicotine analysis, by combining Zr-based metal organic framework (Zr-MOF) and branched polyethylenimine (BPEI)-coated Ru(dcbpy)₃²⁺ through electrostatic interaction. Ru(dcbpy)₃²⁺ integrated by Zr-MOF could be catalyzed by the reaction intermediates SO₄^•-, produced from the co-reactant S₂O₈^2-, resulting in a significant increase in ECL response. Interestingly, SO₄^•- with strong oxidizing ability could preferentially oxidize nicotine, leading to ECL quenching. The constructed ECL sensor based on the Ru-BPEI@Zr-MOF/S₂O₈^2- system displayed ultrasensitive determination of nicotine with a lower detection limit of 1.9 × 10^-12 M (S/N = 3), which is three orders lower than previously reported ECL results and 4-5 orders lower than that of other types of method. This method puts forward a new approach for building efficient ECL system with greatly improved ECL sensitivity for nicotine detection.