Development of a Cigarette Tobacco Filler Standard Reference Material

Mechanistic Insight into a Novel Ultrasensitive Nicotine Assay Base on High-Efficiency Quenching of Gold Nanocluster Cathodic Electrochemiluminescence

Monitoring nicotine concentrations in human fluids is extremely crucial owing to the harmful effect of nicotine on human health. Herein, it is shown that nicotine could quench the cathodic electrochemiluminescence (ECL) of gold nanoclusters (AuNCs) with high efficiency. The ECL quenching mechanism of nicotine was studied in detail using various experimental tools and theoretical calculations. It was concluded that the strongly oxidizing intermediate SO₄^•-, produced from K₂S₂O₈, could oxidized nicotine, resulting in ECL emission quenching. On the basis of this high-efficiency ECL quenching of the AuNCs/K₂S₂O₈ system, a recyclable, ultrasensitive, and selective ECL sensing platform for nicotine detection was proposed. Even in the absence of any complex signal amplification techniques, the ECL sensor for nicotine detection showed an unprecedentedly low detection limit of 7.0 × 10^-13 M (S/N = 3) and a wide linear range over 8 orders of magnitude. Most remarkably, it could be successfully used for nicotine detection in human urine samples. This is expected to promote the investigations and applications on nicotine-related diseases. We believe that the proposed ECL platform can hold great prospects for commercialization in biomedical fields and tobacco industries.

Fluorescent carbon nanodots-based artificial tongue for determining and discriminating cigarettes

Smoking can cause cigarette-related diseases and pose serious threat to human health. Its dangers can be effectively controlled by discriminating cigarettes and monitoring cigarette quality. Herein, a kind of artificial tongue technique based on the indicator displacement assay (IDA) was developed and applied to determine and discriminate cigarettes and their main ingredients (saccharides, organic acids and nicotine). This method was constructed using carbon nanodots (CDs) as a fluorescent indicator and various concentrations of silver ion (Ag⁺) as a fluorescent regulator. A cigarette extracting solution was prepared to interact with an artificial tongue and produce fluorescence fingerprints. Twenty-nine kinds of cigarettes can be well discriminated in terms of category (flue-cured cigarette, blended cigarette and cigar), brand, origin (domestic or foreign cigarettes) after processing and visualizing the response fingerprints. The artificial tongue fluorescent sensor array can sensitively detect nine kinds of tobacco-based chemical ingredients and discriminate them between different concentrations. The as-prepared fluorescent artificial tongue is a promising platform for monitoring cigarette quality and controlling the harmful effects of smoking because of its cheap material requirements, simple operation, and good performance.

Simultaneous determination of multiple components in cigarettes by mechanochemical extraction and direct analysis in real time mass spectrometry in minutes

A simple, rapid and high throughput analytical approach with combination of mechanochemical extraction (MCE) and direct analysis in real time mass spectrometry (DART-MS) analysis was developed for the simultaneous determination of multiple chemical components in cigarette fillers. Different kinds of substances including nicotine, cigarette alkaloids, carbohydrates, organic acids, humectants and other additives were successfully extracted using MCE and detected by high resolution DART-MS. Six solvents of various polarities were compared during MCE process and significant differences were observed. Different brands of cigarettes as well as standard research cigarette exhibited distinctive chemical features and DART-MS fingerprints. Principle component analysis showed clear differentiation among different cigarettes extracted with the same solvent and different solvent extracts of the same type of cigarette. The putative chemical formulas were proposed based on accurate m/z values with <10 ppm mass errors. The relative contents of nicotine and other identified substances were compared and significant differences were observed among cigarettes of different locations. The whole procedure of MCE combined with DART-MS only takes minutes from raw cigarette fillers to obtaining the semi-quantitative results. The operation is simple and high throughput, providing an efficient method to analyze cigarette composition, and to establish a methodology to acquire the rapid cigarette fingerprints for quality control.