Journal of Analytical Methods in Chemistry最新文献

Soil metabolites are not only the integrated expression of soil biological activities but also the pivotal drivers of biogeochemical cycling, thereby significantly influencing the formation of crop quality. This study established an improved ultra-performance liquid chromatography (UPLC) fingerprint with chemometrics for characterizing the nonvolatile metabolite profiles of soils from geographical locations defined by different tobacco flavor styles in Guizhou. The homogenization extraction and then UPLC analysis were selected as the optimal system due to their superior repeatability and reproducibility, with intraday and interday RSD% of the common peaks (retention time and peak area) below 2.75%. The fingerprint profiling was established using 18 soil samples from three locations, namely the honey-sweet region I, II, and the fresh-sweet region. Thirty common peaks were identified, with similarities ranging from 0.809 to 0.956. Then, the common peaks were subjected to chemometrics analysis. These results indicated that significant differences were observed by principal component analysis (PCA), and 17 characteristic metabolites were viewed as primarily discriminatory by partial least squares discriminant analysis (PLS-DA). The total content of characteristic metabolites followed a trend of honey-sweet region II > honey-sweet region I > fresh-sweet region, with individual metabolites generally higher in the honey-sweet region. Finally, external validation using the hierarchical cluster analysis (HCA) and Fisher discriminant analysis (FDA) model accurately classified four soil samples, further confirming the representativeness of the characteristic metabolites. This study supplies a theoretical foundation to understand the relationship between tobacco flavor formation and soil metabolism, showing great potential applications in agricultural research.

This study developed a method for simultaneously detecting 10 mycotoxins in Dendrobium officinale using the QuEChERS technique combined with ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The method was optimized for sample purification, pretreatment, chromatographic conditions, and mass spectrometric settings. It effectively addressed the matrix effects from impurities like pigments and cellulose. The validation of the method showed good linearity (R ² > 0.990), with limits of detection (LODs) ranging from 0.23 to 8.61 μg kg^-1 and limits of quantification (LOQs) from 0.77 to 28.7 μg kg^-1. Average recoveries for the 10 mycotoxins ranged from 77.9% to 98.5%, with relative standard deviations (RSD) between 2.26% and 8.28%. The method demonstrated high accuracy, precision, and suitability for large-scale screening of mycotoxins in Dendrobium officinale. When applied to 84 samples, the contamination rate was 2.38%, with the main contaminants being AFB1, ZEN, and AFG1. This method provides a reliable, cost-effective approach for detecting mycotoxin contamination in traditional Chinese medicine.

Mango peel is one of the main byproducts in mango processing. In order to improve the utilization and added-value of mango peel, effects of the ultrasound-assisted enzymatic method on the extraction rate of mangiferin from mango peel were investigated by single-factor tests (enzyme addition amount, enzymolysis time, ethanol concentration, ultrasonic temperature, ultrasonic power, and ultrasonic time), and the extraction process was optimized by Box-Behnken response surface. The antioxidant activity and antidiabetic assay of mangiferin in vitro were studied. The results showed that enzymolysis time 44 min, enzyme addition amount 0.1%, ethanol concentration 70%, ultrasonic power 300 W, ultrasonic temperature 66°C, and ultrasonic time 45 min were the optimal extraction process parameters. Under these conditions, the extraction rate of mangiferin was 3.63% ± 0.04%, which was not significantly different from the model prediction value (3.71%), and it was 3.90 times and 1.78 times that of single cellulase and ultrasonic extraction, respectively. Within the test concentration range, the scavenging rate of mangiferin for DPPH·, ABTS⁺·, and O₂ ^-· increased with the increase of its mass concentration, and the EC₅₀ values were 0.03829 mg/mL, 0.06032 mg/mL, and 0.04949 mg/mL, respectively, which were slightly higher than those of Vc. Meanwhile, mangiferin exhibited inhibitory activity effects on α-amylase and α-glucosidase, with IC₅₀ values of 0.1952 and 0.08696 mg/mL, respectively. Results indicate that the mangiferin in mango peel had strong bioactivity. The study provides a theoretical reference for the efficient extraction of mangiferin from mango peel and provides a scientific basis for further realizing the high-value utilization of mango processing waste.

Lauraceae plants are diverse in species and rich in volatile components, which possess functions such as insect repellency, antioxidant activity, and antibacterial properties. However, currently, the methods for analyzing the volatile components of Lauraceae plants are relatively single. The essential oils are mainly extracted by steam distillation, but the pretreatment is relatively complex and cumbersome. Therefore, it is essential to find a simple and cost-effective method. By comparing different extraction methods, HS-SPME-GC-MS was selected as the optimal extraction condition. Regarding Head-space Solid-Phase Microextraction and Gas Chromatography-Mass Spectrometry (HS-SPME-GC-MS), single-factor condition optimization and response surface analysis were carried out for different fiber coatings, equilibrium time, extraction temperature, and extraction time. Eventually, 75-μm CAR/PDMS fiber head was chosen, with an equilibrium time of 15 min, and extraction was conducted at 70°C for 57 min as the optimal HS-SPME extraction conditions. Furthermore, a differential analysis of the volatile components of five Lauraceae plants from different genera was performed, and differential metabolites were screened out respectively. This can effectively separate Cinnamomum and Litsea from the other three genera, providing certain assistance for the chemotaxonomy of the volatile components of Lauraceae plants and the subsequent development of medicinal plant resources.

The fixed-dose combination (FDC) of ibuprofen (IBU) and paracetamol (PAR) has emerged as a preferred option in pain management, owing to its distinct practical advantages. Both drugs have well-documented efficacy and safety profiles, providing synergistic pain relief through complementary mechanisms of action. IBU not only offers central analgesic effects but also inhibits cyclooxygenase (COX) enzymes, particularly COX-1 and COX-2, thereby reducing prostaglandin synthesis at the site of pain to deliver both analgesic and anti-inflammatory benefits. Despite the growing use of this combination, a comprehensive review focusing on the analytical methods for its determination has not yet been published. This review aims to bridge that gap by presenting an extensive compilation of documented analytical methods for the quantification of IBU and PAR in both bulk and pharmaceutical formulations. It serves as a valuable resource for researchers and professionals seeking detailed insights into the diverse techniques employed for accurate and precise analysis of these FDCs. Through a systematic search of major scientific databases, including Science Direct, Springer Link, PubMed, Scopus, and Google Scholar, the review identifies the most commonly utilized methods, such as high-performance liquid chromatography (HPLC), gas chromatography (GC), high-performance thin-layer chromatography (HPTLC), ultraviolet (UV)/Visible spectrophotometry, Fourier-transform infrared spectroscopy (FTIR), and micellar electrokinetic chromatography (MEKC). Notably, HPLC and UV/Visible spectrophotometry were the most frequently reported, each accounting for 37.9% of studies. By consolidating these analytical approaches, this review highlights the state-of-the-art methodologies available for the determination of IBU/PAR FDCs and underscores its novel contribution as a definitive reference for future research and development in this field.

A novel, sensitive, and efficient method was developed for the determination of paraquat in soil samples, centered on solid-phase microextraction using hollow fiber-supported ZIF-8@GO reinforced sol-gel combined with UV-Vis spectrophotometry at 257 nm. Silica-based ZIF-8@GO was synthesized through sol-gel technology by reacting tetraethyl orthosilicate (TEOS) with hydrochloric acid (HCl) as a catalyst. The resulting solution was injected into hollow polypropylene fiber segments for in situ gelation. Key microextraction parameters, such as the donor phase pH and volume, stirring rate, extraction time, and desorption conditions (solvent type and volume), were systematically studied and optimized. Under optimal conditions, the method demonstrated linearity within the range of 0.5-2000 μg L^-1, with a correlation coefficient of 0.999. The relative standard deviation for seven replicate measurements at a concentration of 600 μg L^-1 paraquat was 0.4%. A preconcentration factor of 631 and a detection limit of 0.15 μg L^-1 were achieved. Validation of the method was conducted by analyzing soil samples from various sites, yielding recoveries between 96% and 105% with low relative standard deviations, indicating its high accuracy and reliability in detecting trace levels of paraquat.

Dipeptidyl peptidase IV (DPP IV), one of the most essential peptidase, is widely distributed in various organs and tissues of the human body, which affects protein stability by acting on peptide bonds at the end of peptide chains and is further involved in physiological processes such as cellular metabolism and signaling. Recent studies have shown that DPP IV is not only involved in normal physiological processes but also closely related to various pathological processes, making it an important target for the treatment of metabolic diseases. Deciphering the relevance of DPP IV to human diseases and screening the inhibitors of DPP IV requires reliable tools, which can sense the function of this key enzyme in complex biological samples. Therefore, we aimed to construct a simple and easy-to-use assay for human DPP IV activity in a living cell system to achieve highly sensitive and selective detection of DPP IV function and further screening for its inhibitors. An easy-to-use assay for DPP IV function at the cellular level with a specific fluorescence probe toward DPP IV using a fluorescence microplate reader was the first to be established. Then, the experimental conditions were systematically optimized in terms of cell density, concentrations of probe, and incubation time. After that, the efficacy of the positive DPP IV inhibitors was evaluated by utilizing the optimized easy-to-use assay. Overall, this easy-to-use assay exhibited good precision, robustness, high throughput, and reliability. In conclusion, a straightforward and user-friendly method has been developed for detecting DPP IV activity in live cells, enabling accurate assessment of DPP IV function and efficient screening of inhibitors. This method may hold significant implications for advancing understanding of the relationship between DPP IV and disease progression, early disease diagnosis, and personalized drug therapy.

The use of human growth hormone (hGH) by athletes remains widespread despite being banned by the World Anti-Doping Agency (WADA). Current commercial ELISA kits for the determination of hGH are predominantly based on the sandwich format of this method, which allows the analysis of the whole hGH molecules, but not their fragments. The abuse of these fragments by athletes is the current trend in doping. Therefore, a competitive ELISA format is needed; however, only a limited number of kits on the market are based on this principle. Furthermore, these kits are designed to detect and quantify hGH only in blood plasma, serum or tissue cultures. When analysing a nutritional supplement containing hGH using one of these ELISA kits, a false negative result was observed. In the present work, two competitive ELISA methods for the detection of hGH in illegal nutritional supplements were developed. The development of the methods involved the selection of suitable immunoreagents and their combinations with subsequent optimisation of the conditions for their use. The methods were then characterised (with LOD 0.4 and 18.4 ng/mL, according to the primary antibody) and applied to analyse real nutritional supplements. In all 34 samples suspected of containing hGH, the hormone was detected using both ELISA methods and subsequently confirmed by LC-UV and LC-MS. Therefore, the newly developed ELISA methods could become a valuable tool for the police in identifying illegal preparations.

Saffron (Crocus sativus L.), an exceptionally valuable and expensive spice on an international scale, has become the target of a rapid increase in fraudulent practices. In an effort to decrease expenses, stigmas of safflower (Carthamus tinctorius), which closely resemble saffron, are often added to pure saffron as a typical method of adulteration. Hence, by quantifying the extent of eugenol modifications in the samples and employing ion mobility spectrometry (IMS) to identify and quantify these adulterants in saffron, the objective of this research has been accomplished. The analysis of eugenol showed a significant increase in peak intensity as the concentration of safflower increased in laboratory-prepared samples of pure saffron and safflower as well as the mixture of them (25%, 50%, 75%, and 100%, v/v). In the subsequent phase, a total of 20 saffron samples procured from nearby markets were examined under an optical microscope to identify any adulteration with safflower. Five samples, which included saffron containing safflower at varying concentrations (8.3%, 14.9%, 19.4%, 25.4%, and 33.7% W/W), were chosen for additional IMS analysis. The results showed that the peak intensity of eugenol climbed from 0.20 to 0.28 mV by augmenting the safflower content in saffron. Therefore, by increasing the level of safflower contamination in saffron, the concentration of eugenol in the IMS rose. The outcomes demonstrated that the selection method effectively detects saffron adulterated with safflower, improving both precision and specificity, and could aid in defining standard quality control procedures for saffron authenticity and quality.

Background and Objectives: Liver fibrosis results from chronic inflammation. Qijia Rougan decoction, a traditional Chinese medicinal formulation, shows hepatoprotective potential, yet its mechanisms remain unclear. This study aims to investigate its antifibrotic effects and underlying mechanisms. Methods: Rat liver fibrosis was induced by carbon tetrachloride (CCl₄) and ethanol exposure. Histopathological assessment was performed using hematoxylin-eosin (HE) and Masson's trichrome staining. Hepatic stellate cell (HSC) activation and autophagic processes were examined through western blot analysis, immunofluorescence staining, and other in vitro assays. Components of Qijia Rougan decoction were analyzed by BATMAN-TCM platform. The pharmacological network was constructed using BATMAN-TCM platform, while disease-related targets were identified through DisGeNET database. Pathway enrichment analysis was conducted using KEGG pathway database. Results: Significant reductions in hepatic index and serum biomarkers (ALT, AST, ALP, TBA, and γ-GT) were observed following Qijia Rougan decoction treatment, with maximal efficacy at 6 weeks. The decoction downregulated of LC3B and α-SMA expression in fibrotic tissues. In vitro, it suppressed LPS-induced α-SMA expression and autophagosome formation in HSC-T6 cells. Network pharmacology analysis of Qijia Rougan decoction identified 274 bioactive compounds and 12,883 potential targets, with pathway analysis indicating PI3K/AKT signaling as the predominant regulatory mechanism. Conclusion: Qijia Rougan decoction alleviates liver fibrosis, potentially by inhibiting HSC activation and autophagy processes via PI3K/AKT/mTOR pathway.