International Journal of Analytical Chemistry最新文献

A simple, sensitive, precise, and environmentally safe spectrophotometry method was developed and validated for the determination of organophosphate in various fruits and vegetables using a UV-Visible spectrophotometer using a magnesia mixture. The volume of reagent used for analysis and the stability of the color complex were also optimized. The drug showed a stable white color complex at 420 nm. The greenness of the methods was estimated using an ecoscale (84), the Green Analytical Procedure Index, and AGREE (0.89), which were found to be excellent green method based on spectrophotometric determination. The method was validated using ICH guidelines and has acceptable values for linearity (0.5-2.5 mg/ml), accuracy (98.5-102.5%), precision, robustness, limit of detection (0.16 mg), and limit of quantification (0.486 mg). The concentration of the organophosphate in the analyzed sample was in the range of 0.003 to 2.45 mg. Altogether, the proposed green analytical method was found to be a simple, selective, sensitive, accurate, and ecofriendly method for the analysis of organophosphate in various fruits and vegetables.

[This retracts the article DOI: 10.1155/2022/6015826.].

[This retracts the article DOI: 10.1155/2022/5087896.].

[This retracts the article DOI: 10.1155/2022/2323534.].

Teff [Eragrostis tef (Zuccagni) Trotter] is a cereal grain originating in Ethiopia as a staple food for millions of people. Its grain is a gluten-free superfood and got acceptance as a medicinal ingredient. Therefore, it is worthwhile to determine the antioxidative activities and L-ascorbic acid contents of teff grain and its baked food (injera). This study aimed to determine the ascorbic acid contents and antioxidant activities in the aqueous extract of the white and brown teff grains and their injera samples using iodimetric titration and UV-Vis spectrophotometric methods, respectively. The ascorbic acid contents in the white and brown teff ranged from 67.9-112.6 mg/100 g and 69.2-117.2 mg/100 g, respectively, and those in injera of the selected teff samples ranged from 30.5-32.9 mg/100 g and 37.3-43.0 mg/100 g, respectively. The antioxidant activities ranged from 1.26-7.04 μmol AAE/g for the white teff grains, 1.44-6.29 μmol AAE/g for the brown teff grains, 1.81-2.47 μmol AAE/g for white teff injera, and 3.89-4.86 μmol AAE/g for the brown teff injera samples. Findings of the present study have revealed that white teff and brown teff grains and their injera were found to have a higher content of ascorbic acid than commonly consumed grains and vegetables. No significant difference (α = 0.05) has been observed between the two varieties of teff grains with respect to the ascorbic acid content and antioxidant activities. However, there was a statistically significant difference (α = 0.05) in the ascorbic acid content and antioxidant activities between the teff grains and their injera samples. Therefore, this study indicated that teff grains and injera are rich in ascorbic acid content and antioxidant activities as compared to other cereal grains and are very crucial for human nutrition and health.

Background: Mitogen-activated protein kinase 3 (MAPK3) mediates the onset, progression, metastasis, drug resistance, and poor prognosis in various malignancies, including glioma, liver, ovarian, thyroid, lung, breast, gastric, and oral cancers. Negative regulation of MAPK3 expression using miRNAs has led to therapeutic effects in cancer.

Objectives: The present study performed molecular docking and dynamics simulation to identify potential MAPK3 inhibitors from natural flavonoids, possibly leading to drug development in cancer therapy.

Methods: A computational drug discovery approach was performed using the AutoDock tool to identify potential MAPK3 inhibitors from 46 plant-based flavonoids. A cross-validation study was executed using the Schrödinger Maestro docking tool. Molecular dynamics (MD) was executed to evaluate the stability of docked poses between the top-ranked compounds and the MAPK3 catalytic domain. Interactions among the most potent MAPK3 inhibitors and residues within the receptor's active site were studied using the BIOVIA Discovery Studio Visualizer before and after 100 ns MD simulations.

Results: Kaempferol 3-rutinoside-4'-glucoside, kaempferol 3-rutinoside-7-sophoroside, rutin, and vicenin-2 exhibited a magnificent binding affinity to the receptor's active site. In addition, the stability of the docked poses of these compounds seemed to be stable after ∼45 ns computer simulations.

Conclusion: The present study suggests that kaempferol 3-rutinoside-4'-glucoside, kaempferol 3-rutinoside-7-sophoroside, rutin, and vicenin-2 could strongly bind to the MAPK3 catalytic site and could be assigned as a potent inhibitor for MAPK3. These findings may be helpful in the treatment of various cancers. However, further validation experiments are needed.

Materials and methods: The metabolomics-proteomics of sixty patients with T2DM were acquired by high-performance liquid chromatography (HPLC). In addition, some clinical features, containing total cholesterol (TC), triglycerides (TG), hemoglobin A1c (HbA1c), body mass index (BMI), and low-density lipoprotein (LDL) together with high-density lipoprotein (HDL), were determined via clinical detection strategies. Abundant metabolites and proteins, respectively, were identified with the analysis of liquid chromatography tandem mass spectrometry (LC-MS/MS).

Results: 22 differentially abundant metabolites and 15 differentially abundant proteins were determined. The analysis of bioinformatics suggested that the differentially abundant proteins were commonly associated with the renin-angiotensin system, vitamin digestion and absorption, hypertrophic cardiomyopathy, and so on. Furthermore, differentially abundant metabolites were amino acids and were associated with the biosynthesis of CoA and pantothenate, together with the metabolisms of phenylalanine, beta-alanine, proline, and arginine. Combination analysis revealed that the vitamin metabolism pathway was predominantly affected.

Conclusions: DHS syndrome can be separated by certain metabolic-proteomic differences, and metabolism is particularly prominent, especially in vitamin digestion and absorption. From the molecular level, we provide preliminary data for the extensive application of TCM in the study of T2DM, and at the same time benefited in a sense diagnosis and treatment of T2DM.

A novel enzyme-based biosensor for glucose detection is successfully developed using layer-by-layer assembly technology. The introduction of commercially available SiO₂ was found to be a facile way to improve overall electrochemical stability. After 30 CV cycles, the proposed biosensor could retain 95% of its original current. The biosensor presents good detection stability and reproducibility with the detection concentration range of 1.96 × 10^-9 to 7.24 × 10^-7 M. This study demonstrated that the hybridization of cheap inorganic nanoparticles was a useful method in preparing high-performance biosensors with a much lower cost.

A rapid HPLC-UV method for the determination of three organic acids (neochlorogenic acid, chlorogenic acid, and cryptochlorogenic acid) in Polygoni Vivipari Rhizoma (PVR) by one marker was developed. The sample was prepared by effervescence-assisted matrix solid-phase dispersion (EA-MSPD). The separation of compounds was performed on a Poroshell column. The equal absorption wavelength was set as follows: 292 nm (0∼7 min) and 324 nm (7∼10 min). The analytical time including sample extraction and HPLC separation time was 12 min. The analytical method validation such as accuracy (recoveries 99.85%-106.29% and RSD < 2.9%), precision (RSD < 1.3%), reproducibility (RSD < 1.7%), and stability tests (RSD < 0.7% in 24 h) proved that the established HPLC method was suitable for determination of three organic acids in PVR. The contents of three analytes obtained by the external standard method with three markers and the equal absorption wavelength method with one marker were similar (RSD ≤ 2.0%). The developed method, which is rapid and reference compound saving, is an improved quality evaluation method of PVR.

[This retracts the article DOI: 10.1155/2022/4996265.].