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A direct comparison with reverse-phase LC-MS/MS and GC-MS/MS was conducted for comparative purposes. The representative commodities selected for this evaluation were pepper and tomato. Furthermore, possible oxidative degradation during the sample milling step was also evaluated and avoided by the application of crio-milling conditions and ascorbic acid addition. By the proposed procedure, captan and folpet were recovered in both matrices at the 84%-105% range and with an RSD below 8% at two concentration levels 10 and 50 μg/kg. On the contrary, with GC-MS/MS, captan and folpet were not recovered, and, as a consequence, their evaluation was possible only by THPI and PI. In the case of LC-MS/MS a significant decrease in the sensitivity was observed compared to SFC-MS/MS. Other validation parameters evaluated were satisfactory. This new approach can assess the correct analysis of captan and folpet at low concentrations in fruits and vegetables.Black phosphorus quantum dots (BP QDs) were prepared through a solvothermal exfoliation method in alkaline N-methyl-2-pyrrolidinone. The BP QDs induce distinct chemiluminescence (CL) of alkaline luminol directly. A possible reaction mechanism is proposed by the study of CL spectrum, ultraviolet-visible absorption spectra, electron paramagnetic resonance spectra as well as radical scavenging experiments. The presence of BP QDs significantly increases generation of active oxygen species, which oxidize luminol and lead to intense CL emission at 425 nm. The reaction of luminol with BP QDs are specifically catalyzed by cobalt (II) ion, this presents a sensitive CL method for cobalt (II) ion. A linear response range extends from 2.5 to 2000.0 pmol/L cobalt (II) ion and a detection limit of 0.7 pmol/L (3sb) is acquired. The method displays a good precision approved by a relative standard deviation of 1.9% at 100.0 pmol/L cobalt (II) ion solution (n = 11). A preliminary application of the method was conducted by successful determination of cobalt amount in silica gel and rain water samples.The analysis of aroma composition in scented plants and natural products to probe their quality and safety is an important topic, particularly when such ingredients are intended for long term use as in food or cosmetic products. The development of fast, comprehensive, and effective analytical tools for essential oil analysis in such complex mixtures is of interest and moreover when present in blend of several oils, as typical in case of nutraceuticals or cosmetics. Comprehensive studies of volatiles could be achieved via coupling the separation power of multidimensional chromatography with selective detectors as mass spectrometers. This strategy enables high-throughput and global analysis of hundreds of metabolites in a single step. Different multidimensional setups such as GC × GC and LC-GC in addition to various chemometric approaches applied for essential oils analysis form a fundamental part of this review. AHPN agonist order Asides, applications of multidimensional chromatography for essential oils chemotyping, enantio-separation, quality control and adulteration detection in the different matrices are also presented.In this work, an unmodified homogeneous electrochemical sensor based on electrochemical bonding and catalytic hairpin assembly (CHA) was first constructed for the high sensitivity detection of Hg2+. Herein, tetraferrocene, a synthesized compound, was used as a signal marker that modified both ends of the hairpin probe to amplify the electrochemical signal. The interaction of T-Hg2+-T could induce the catalytic self-assembly of hairpins by means of auxiliary DNA. The rigid DNA triangle that was formed easily reaches the electrode and induced Au-S self-assembly assisted by potential, allowing tetraferrocene to reach the electrode surface and generate a sensitive electrochemical signal. CHA and tetraferrocene signal markers accomplished dual signal amplification, and the limit of detection was 0.12 pM. Differential pulse voltammetry experiments in the presence of tetraferrocene redox indicator show that the linear response range of electrochemical biosensors to mercury ions is 0.2-2000 pM, This technology offers good selectivity and high recognition efficiency for the detection of mercury ions and has broad application prospects in actual sample detection.Over recent years, metabolomics has been featured as the state-of-the-art technology that successfully opens the paths to understanding biological mechanisms and facilitating biomarker discovery. However, the inherent dynamic and sensitive nature of the metabolome have been challenging the accuracy of capturing the timepoints of interest while using biofluids such as urine and blood. Hair has thus emerged as a valuable analytical specimen for the long-term and retrospective determinations. Unfortunately, notwithstanding the apparent interest on global hair metabolomics, very few studies have engaged in the optimisation of the extraction strategy. In this study, we systemically investigated the extraction procedures for hair metabolome using a single factor experimental design. Three pH values (acidic, neutral, and basic) in aqueous solution, six extraction solvents (methanol, acetonitrile, acetone, phosphate-buffered saline, deionised water, and dichloromethane), different compositions of selected solvent mixradient.Platinum group elements (PGEs) are among the least abundant in the continental crust. They have become excellent tracers of anthropogenic activities, particularly due to their use in catalytic converters or in the medical industry. However, their quantification in environmental matrices is still problematic because of their low concentrations combined with the presence of interfering elements. Preconcentration methods are therefore necessary to measure accurate concentrations. In this study, the quantification of Ir, Rh, Ru, Pd and Pt was studied in depth by focusing on two resins AG MP-1 (anion exchange) and Purolite® S-920 (chelating) with the aim of developing passive Diffusive Gradients in Thin films (DGT) samplers as in-situ pre-concentration tools. The characteristics of both resins (e.g. adsorption, elution, selectivity, etc.) were studied and the diffusion coefficients of PGEs in different matrices were determined. For the first time, carcinostatic platinum-based drugs were also studied. Better rates and percentages of adsorption were observed for S-920 while AG MP-1 was more selective with regard to spectral interferents and easier to elute.