Journal of Analytical Methods in Chemistry最新文献

This study investigates the optimal conditions to enrich the phenolic content of the extract from Pandanus amaryllifolius leaves and evaluates the bioactivities of this enrichment. The phenolic enrichment was prepared under optimized conditions using the response surface methodology (RSM) with the Box-Behnken design. The antioxidant properties were assessed using DPPH and hydroxyl radical scavenging assays, while the NO production inhibition was measured in LPS-stimulated RAW 264.7 macrophage cells. Results indicated that the phenolic enrichment showed potent antioxidant activity comparable to ascorbic acid and catechin and significantly higher NO inhibition than the separated nonalkaloid and alkaloid fractions. The study also highlights the synergistic effect of phenolic and alkaloid compounds on the antioxidants and anti-inflammatory activities of the phenolic enrichment from Pandanus amaryllifolius leaves.

The Feng-Liao-Chang-Wei-Kang (FLCWK) capsule is a nationally protected Chinese patent medicine for the treatment of colitis. However, the potential active components and the pharmacological mechanism underlying the anticolitis effect of the FLCWK capsule remain unclear. This study aimed to reveal the active ingredients and possible anticolitis mechanism of the FLCWK capsule using an integrated approach combining mass spectrometry and network pharmacology analysis. Ultra-performance liquid chromatography plus Q-Exactive Orbitrap tandem mass spectrometry (UPLC-Q-Exactive Orbitrap MS) was applied to identify the components of the FLCWK capsule. A network pharmacology study, including target gene prediction and functional enrichment, was applied to screen the active ingredients of the FLCWK capsule and explore its potential mechanism for the treatment of colitis. A total of 115 components were identified in the FLCWK capsule. Network pharmacology results showed that 46 of these compounds with good bioavailability and drug-likeness, such as 4',5-dihydroxyflavone, pinostrobin, naringenin chalcone, apigenin, and morin, were selected as active ingredients. The active ingredients may act on 352 core protein targets, including EGFR, AKT1, PIK3R1, PIK3CB, and MAPK1, thereby modulating relevant pathways, such as MAPK and PI3K-Akt signaling pathways, and thus alleviating inflammation and intestinal damage in colitis. This study provided a useful approach to identify active components and the anticolitis mechanism of the FLCWK capsule and built up a reliable foundation for its clinical treatment.

Background: Hirudin is a major active ingredient of the traditional Chinese medicine leech. It has been proved to have good antithrombotic and anticoagulant effects. Objective: To determine the tissue distribution of hirudin and its pharmacokinetics in vivo by ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods: A total of 21 SPF adult New Zealand rabbits were acclimatized for 1 week, and one was randomly selected as a blank control, while the remaining 18 were randomized to the control group and the model group. The heart, liver, spleen, lung, kidney, brain, plasma, blood vessels, and colon tissues were taken by execution at 1, 3, and 6 h. The samples were assayed using the natural hirudin standard as an external standard. Results: The established UPLC-MS/MS method with good precision, accuracy, recovery, and stability of hirudin proved to be reliable. The correlation between different concentrations of natural hirudin standard and the response value was R ² ≥ 0.9997. The results of the distribution of various tissues showed that hirudin in the two groups had the highest content in plasma and blood vessels, followed by spleen, lung, and liver tissues, and was weaker in the brain and the heart, and the content of hirudin in the control group was higher than that of the model group, and the difference was statistically significant. Conclusion: The absorption and metabolism of hirudin in rabbits with carotid artery injury mainly acted through vascular tissues and blood, and normal rabbits mainly metabolized it through spleen, lung, and liver.

Pharyngiyan tablet is a traditional Chinese medicine (TCM) renowned for its efficacy in moisturizing the lungs, clearing the throat. However, it exhibits quality variations due to discrepancies in regulatory standards and challenges in comprehensive evaluation. In this study, ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) was used to qualitatively analyze the chemical composition of pharyngiyan tablets. Full composition analysis detected 131 chemical constituents. Gallic acid, paeoniflorin, rutin, baicalin, and harpagoside were identified as quality control (QC) indexes through rational screening. These indexes were selected based on their effectiveness in demonstrating differences, stability after processing, specificity, and cost-effectiveness in measurement. For the multimetric quality assessment of the five screening components, a high-performance liquid chromatography with diode array detector (HPLC-DAD) method with wavelength switching was developed. A total of 104 batches of samples from 10 manufacturers were included in the analyses. The content of each ingredient varied significantly across enterprises and batches, with certain enterprises characterized by inferior drug feeding, deviation from prescribed ingredient amounts, and nonstandardized feeding practices. Overall, aquality assessment method was established to provide a basis for the market regulation and quality assessment of pharyngiyan tablets.

A reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed for simultaneous determination of triclabendazole (TCB) and ivermectin (IVM) in pharmaceutical dosage form. A mobile phase consisting of acetonitrile/water (50:50 v/v) with a flow rate of 1.5 mL/min was used for chromatographic separation of the mixture of TCB and IVM. The developed method was found to be linear with the correlation coefficient (r = 0.999) for TCB and IVM in the presence of suspension. The limit of quantitation (LOQ), robustness, specificity, accuracy, and precision were validated for the developed method. The peak areas of five replicates of the samples were recorded, and the acceptance rate of suspension recovery was 98%. The intraday accuracies for TCB and IVM were 98.71% and 100.79%, respectively, with a relative standard deviation (RSD) of 0.87%. The limits of detection (LOD) of TCB and IVM were 0.058 mg/mL and 0.112 μg/mL, respectively, while the LOQ of TCB and IVM were 0.178 μg/mL and 0.340 μg/mL, respectively. The method's % RSD for intra- and interday precision was deemed satisfactory. The developed method could be utilized for the determination and measurement of TCB and IVM in other samples.

The diverse industrial use of chlorinated paraffins (CPs) have led to their environmental dispersion, and special attention has been paid to their ecotoxicology. Among them, short-chain chlorinated paraffins (SCCPs) have been listed as potential persistent organic pollutants (POPs). However, currently, technical CPs produced by manufacturers are usually labeled by their chlorination degree, but such structural label is not enough to reflect CPs' environmental fate and toxicity. Ecotoxicology research suggested that the chain length, chlorination degree and the chlorine distribution pattern are all factors that can determine CPs' environmental fate and toxicity. Herein, we present a cost-effective method for the structure characterization of technical CPs. By using direct injection mass spectrometry with data deconvolution, chain length distribution and homologous distribution in technical CPs mixture can be delineated. By using ¹H NMR with chemometrics tools, the chlorine distribution pattern can be elaborated. Combining the abovementioned two analytical strategies, structural information at different levels that related to CPs' environmental fate and toxicities were revealed. This method is expected to be easily applied in both industry and academia, aiming for quality control of technical CPs, by permitting only nontoxic or noncarcinogenic CPs into industrial use.

Dopamine (DA) is a catecholamine neurotransmitter secreted by the human adrenal medulla and is related to many medical diseases. The rapid and sensitive detection of DA levels in physiological media is attracting attention. This paper has developed a fluorescence paper-based sensor using CdTe quantum dots (QDs)-rod nanozinc 5, 10, 15, 20-tetra (4-pyridyl)-21H-23H-porphine (nanoZnTPyP) for sensitive and visual detection of DA. After adding DA, the original quenching fluorescence of the CdTe QDs-rod nanoZnTPyP sensor was effectively restored. The detection mechanism may be that the oxidation of DA to the alkaline CdTe QDs-rod nanoZnTPyP solution produced DA-quinine, and the recovery of fluorescence was caused by the electronic effect of DA-quinine and rod-shaped nanoZnTPyP. The detection range is 0.5∼10 nmol/L, and the limit of detection (LOD) is 0.38 nmol/L (S/N = 3). The sensor system was used on paper device to detect significant changes in the fluorescent color of DA at different concentrations. In addition, this method has been successfully used for the determination of DA in human plasma. The sensor system is simple, easy to operate, and has high selectivity for possible DA interfering substances, which provided new ideas for detecting DA and Parkinson's disease, Alzheimer's disease, and other DA-related diseases.

Despite the availability of current resources, the development of medical countermeasures remains crucial in combatting the threat posed by chemical warfare agents, such as organophosphorus compounds (OPs), which are toxic nerve agents requiring rapid medical intervention. Within the available therapeutic arsenal, muscarinic antagonists such as atropine are administered to mitigate the effects of excessive cholinergic system stimulation, which leads to respiratory tract obstruction due to hypersecretions and bronchoconstriction. Tiotropium, an FDA-approved bronchodilator, acts as a muscarinic receptor antagonist and could, therefore, serve as a potential alternative. To assess its potential efficacy in attenuating OP-induced respiratory effects in a murine intoxication model, it was necessary to first characterize its pharmacokinetic properties. A liquid chromatography-mass spectrometry method was developed and validated following ICH M10 guidelines for the quantification of atropine and tiotropium in 10 μL of plasma. The sample pretreatment procedure involved solid-phase extraction. Chromatographic separation was achieved using a fully porous sub 2 μm C18 column. The analysis was completed in just 4 min, with analytes identified and quantified using two selected reaction monitoring transitions. The mean extraction recoveries exceeded 90% for both drugs, and no matrix effect was observed. The lower limits of quantification were 0.5 ng/mL for tiotropium and 1.0 ng/mL for atropine, with an upper limit of 1000 ng/mL. The signal-to-concentration ratio demonstrated recoveries of back-calculated concentrations ranging from 94% to 108% (relative standard deviation (RSD) < 9.0%). Within-run and between-run precisions were both below 8% with accuracies ranging from 87% to 110%. This highly specific and sensitive method has proven useful for analyzing samples from pharmacokinetic studies conducted in mice. Following intraperitoneal administration, the AUC for tiotropium was approximately twice that of atropine, while its Tmax was half as long (4.9 vs. 8.2 min). The terminal half-lives were approximately 7.5 min for tiotropium and 9.8 min for atropine.

Objectives: To establish and validate a sensitive and robust gas chromatography-mass spectrometry (GC-MS) method for the quantification of β-elemene in human plasma and assess the correlation between antitumor effect and β-elemene concentration in vivo. Methods: The chromatographic column was HP-5 ms (30 m × 0.25 mm, 0.25 μm, Agilent, United States of America). The carrier gas was helium (purity > 99.5%). The flow rate was 1.0 mL/min and the total run time was 11.0 min. The plasma sample was pretreated with protein precipitation plus liquid-liquid extraction. Cancer patients were enrolled and their samples were collected for analysis. Results: Calibration range of β-elemene was 200.0-20,000.0 ng/mL, with correlation coefficients > 0.99. The intra- and interday precision and accuracy were less than 5.8% and within the range of -10.4%-6.6%. The exposure level of β-elemene in the responder group ranged from 278.13 to 11,886.27 ng/mL, with a median of 3568.91 ng/mL, while in the nonresponder group, the range was from 675.92 to 9716.52 ng/mL, with a median of 3351.94 ng/mL. No difference was found in the β-elemene exposure level between the two groups (p > 0.05). Conclusions: This method was effectively developed, validated, and utilized to quantify β-elemene in cancer patients. The initial findings indicated no significant relationship between therapeutic efficacy and the concentration of β-elemene.

Headspace-gas chromatography-ion migration spectrometry (HS-GC-IMS) combined with chemometrics was used to analyze the changes in volatile aroma compounds (VOCs) at different production stages of steaming Polygonatum cyrtonema Hua. Fifty-seven representative compounds in the process of steaming were identified, including 17 aldehydes, 15 alcohols, 15 ketones, 5 esters, 3 furans, and 2 acids. After steaming, the content of 21 compounds decreased. Among them, 3 compounds gradually decreased along with an increase in steaming times; they were 1-hexanol dimer, 1-hexanol monomer, and 3-methylbutan-1-ol dimer. The content of 14 compounds increased than before, and that of three, 1-(2-furanyl)ethanone monomer, 2-furaldehyde, and 3-methyl butanal, increased significantly in the steaming times. The VOCs of the different samples can be classified by GC-IMS data combined with principal component analysis (PCA) and heatmap cluster analysis. A reliable prediction set was established by orthogonal partial least squares discriminant analysis (OPLS-DA), and 18 different VOCs with projected variable importance (VIP) greater than 1.0 were screened out, which could be used as differentiating markers. Therefore, HS-GC-IMS and PCA were used to rapidly identify and classify the VOCs in different production stages of steaming P. cyrtonema Hua.