International Journal of Analytical Chemistry最新文献

A novel and simple study outlines the advancement of a straightforward and precise spectrophotometric technique for the determination of Cd (II) ions. This method offers a notable benefit as it is a straightforward procedure that does not require additional purification or concentration of the solvent. The concentration of Cd (II) ions was determined in the presence of bis(indoline-2, 3-dione) thiosemicarbazone (L) at a pH of 12 using Briton-Robinson Buffer. The concentration range for Cd (II) ions in the method follows Beer's law and is between (1.8-17.8) × 10^-5 mol L^-1. The limit of detection is 0.245 μg mL^-1(2.2 μmol L^-1) and the limit of quantification is 0.817 μg mL^-1 (7.3 μmol L^-1). The molar ratio between L and Cd (II) ions was 1:2, ensuring the development of a metal complex. The applied method offers numerous benefits, including its simplicity, affordability, convenience of use, quick detection, minimal use of ligands, and high sensitivity. The sensitivity of the analytical approach was verified by carefully selecting appropriate experimental conditions. Additional insights into the composition and arrangement of the complex produced in a solution containing Cd (II) ions and the ligand (L) have been obtained by isolating and studying the solid complex L-Cd. The solid complex, L-Cd, was determined using analytical methods including elemental analysis, UV-Vis spectra, spectral mass, and thermal analysis.

Magnesium is a cation that plays as an important cofactor in various enzymatic reactions. It is the fourth most abundant cation in the body after sodium, potassium, and calcium. There are various magnesium measurement methods available such as spectrophotometry, atomic absorption spectrophotometry, and inductively coupled plasma-optical emission spectrophotometry. These measurement methods have various advantages and disadvantages in measuring magnesium levels in serum. This study aimed to compare the magnesium measurement results by using three different methods. A total of 221 samples were examined for magnesium levels using spectrophotometry, atomic absorption spectrophotometry, and inductively coupled plasma-optical emission spectrophotometry methods. The results were then grouped into hypomagnesemia, noromagnesemia, and hypermagnesemia according to normal values. The mean and standard deviation were calculated and compared across three different methods. The mean and standard deviation of serum magnesium ion levels measured using spectrophotometry, atomic absorption spectrophotometry, and inductively coupled plasma-optical emission spectrophotometry methods were 1.84 ± 0.43, 1.86 ± 0.43, and 1.85 ± 0.43 (mg/dL), respectively. There were no significant differences (p value > 0.05) in serum magnesium levels using spectrophotometry, atomic absorption spectrophotometry, and inductively coupled plasma-optical emission spectrophotometry measurement methods, indicating similar reliability among the methods.

Elemental impurities in drug products may pose a risk to patient health. Therefore, maintaining the levels of these impurities below certain limits is essential for patient safety. Human albumin solution, one of the parenteral drugs used for many years, is crucial in various treatments. Also, the European Pharmacopoeia specifies limits for potassium, aluminum, and sodium in this drug. Inductively coupled plasma-atomic absorption spectrometry (ICP-AAS) and ICP-optical emission spectrometry (ICP-OES) are used for detecting elemental impurities. However, neither method can simultaneously analyze all three impurities within the pharmacopeial limits. This study aimed to develop a new method for simultaneously detecting the levels of potassium, aluminum, and sodium in human albumin-based drugs using ICP-mass spectrometry (ICP-MS). The limit of detection (LOD), specificity, linearity, repeatability, and accuracy were examined, and the recovery percentage was calculated. For Na, K, and Al elements, detection limits were calculated as 0.0105767 μg/mL, 0.001748 μg/mL, and 2.0568E - 4 μg/mL, respectively. Precision and reliability of this method have been proven by the linearity regression coefficients that were found as 0.999, 0.999, and 0.995 for Na, K, and Al. In addition, repeatability recovery rates were 98.70%, 98.38%, and 90.83%; accuracy analysis results were 101.45%, 94.53%, and 108.83% for 50% level; 98.26%, 93.93%, and 95.83% for 100% level; 100.48%, 95.90%, and 107.22% for 150% level for Na, K, and Al elements, respectively. This study successfully developed and validated ICP-MS for the simultaneous quantitative determination of the levels of potassium, aluminum, and sodium in human albumin solution.

Topological descriptors and QSPR analysis are statistical techniques that are highly beneficial for analyzing various physical and chemical characteristics of molecular graphs without necessitating expensive and time-consuming laboratory experiments. The topological descriptor alters the compound to a number and helps in finding physicochemical properties. It more correctly reproduces the theoretical properties of drugs. In this article, the author investigated colorectal drugs capecitabine, leucovorin, tipiracil hydrochloride, etc. and implemented QSPR analysis. Physical qualities such as molar volume, complexity, polarity, and refractivity are the subject of the current study. The outcomes of this study allow for more effective physical property prediction through the use of QSPR models. First, we calculate Tds and secondly perform QSPR analysis. Current work on TIs and QSPR modeling shows a good correlation with physical properties. Moreover, estimated drug results depict and predict the physical properties in an efficient way.

Acetylcorynoline is an alkaloid isolated from the tubers of Corydalis ambigua Cham. et Schltdl. It has anti-inflammatory properties with the potential to treat Parkinson's disease. However, the use of UPLC-MS/MS for identifying acetylcorynoline in mouse plasma has not yet been explored. The present study aimed to develop a fast and selective method for determining the amount of acetylcorynoline in mouse plasma using UPLC-MS/MS. Plasma samples (10 μL) were prepared using methanol-induced protein precipitation following the addition of aconitine as an internal standard. The chromatographic separation was accomplished using a UPLC HSS T3 column with acetonitrile and 0.1% formic acid as the mobile phase. The analytes were run for 4.0 min in total. The target fragment ions m/z 410.4 ⟶ 350.3 for acetylcorynoline and m/z 646.6 ⟶ 586.5 for internal standard were used for quantification using multiple reaction monitoring mode. The mouse blood was obtained at different time points after intravenous (5 mg/kg) and oral (20 mg/kg) administration of acetylcorynoline. The calibration plots for acetylcorynoline in mouse plasma showed a linear trend over the whole range of 1-2000 ng/mL. Both the intraday and interday precision relative standard deviations were less than 11%. The half-life in mice was found to be 2.6 ± 0.7 h and 2.7 ± 0.8 h following oral and intravenous administration, respectively. The bioavailability was determined to be 58.9%. The pharmacokinetics and bioavailability of acetylcorynoline in mice were effectively analyzed using this UPLC-MS/MS method, which had a runtime of 4 min per sample and required only 10 μL of plasma.

Bistorta amplexicaulis (D.Don) Greene from the family Polygonaceae is an important medicinal plant species. The growing therapeutic use of B. amplexicaulis has led to its population depletion thus requiring its conservation. Herein, an efficient, reproducible and reliable propagation protocol system was established for B. amplexicaulis using nodal segments as explant. Various culture media were tested for the assessment of growth and development of this plant species. On the shoot proliferation and rhizogenesis of regenerated B. amplexicaulis plantlets, the effects of several plant growth regulators (PGRs) were assessed. Direct organogenesis from nodal segments was achieved by culturing the nodal explants on Murashige and Skoog medium supplemented with 2.0 mg·L^-1 6-benzylaminopurine (BAP). Shoot multiplication was widely affected by the kind and concentration of PGRs, and the subculturing of in vitro regenerated shootlets on fresh medium. After incubation for 4 weeks at optimum BAP concentration, cultures were transferred to secondary medium with BAP (optimized concentration) supplemented with different auxins (indole acetic acid, indole butyric acid, and naphthalene acetic acid [NAA]). Murashige and Skoog medium enriched with 2.0 mg·L^-1 BAP showed the highest shoot induction response (83% ± 3.61%) with mean shoot number (4.67 ± 1.45) and shoot length of 4.33 ± 1.45 cm. Growth medium fortified with 1.0 mg·L^-1 α- NAA exhibited maximum rhizogenesis with 4.33 ± 0.88 roots and average root length as 5.50 ± 0.76 cm from regenerated B. amplexicaulis shoots. Acclimatized plants of B. amplexicaulis showed 90% survival. The projected protocol may serve as a treasured tool for the rapid and large-scale multiplication of elite B. amplexicaulis and for germplasm conservation to ensure continuous supply of this plant amid the increasing demand.

Objective: This study aims to use bioinformatics and machine learning algorithms to screen and analyze the key genes involved in venous thromboembolism (VTE) and explore the relationship between these biomarkers and immune cell infiltration. Methods: The gene expression profile with the identifier GSE19151 was downloaded from the GEO database. Differential expression analysis using the limma package was conducted to identify genes that were differentially expressed between VTE and normal samples. Biological activities of these genes were then investigated through GO analysis utilizing the R language package. KEGG and GSEA were also performed to identify key signaling pathways. Furthermore, machine learning techniques were employed to determine hub gene signatures related to VTE, and ROC curves were used to validate the findings. To compare the immune infiltration of healthy and VTE samples, single sample gene set enrichment analysis (ssGSEA) was applied. Lastly, the Spearman correlation coefficient was used to assess the relationship between the expression of hub genes and immune cell infiltration. Results: A total of 628 differentially expressed genes (DEGs) were discovered between the VTE samples and normal samples. GO analysis identified protein polyubiquitination, lysosomal lumen acidification, organellar ribosome, mitochondrial ribosome, ammonium transmembrane transporter activity, and immunoglobulin binding as the processes with the highest abundance of DEGs. KEGG pathway analysis revealed that DEGs were enriched in ribosome, COVID-19, viral infection, oxidative phosphorylation, Parkinson's disease, nonalcoholic fatty liver disease, apoptosis, and cancer. The most prominent KEGG pathways associated with VTE were ribosome, Parkinson's disease, oxidative phosphorylation, Alzheimer's disease, and Huntington's disease according to GSEA findings. DLST and LSP1 were identified as hub gene signatures in VTE by machine learning integrative analysis, and ROC curves confirmed their diagnostic value. Results from ssGSEA indicated a significant difference in the degree of immune cell infiltration between VTE and normal samples, with the expression of DLST and LSP1 positively correlated with the content of some immune cells. The R package, code, and analysis results used in this paper are available on https://github.com/doctorlaby/my-project. Conclusion: Our research is the first to utilize machine learning techniques in identifying DLST and LSP1 as significant biomarkers of VTE. With our findings, we have uncovered new insights into the underlying causes of VTE and potential treatments for affected patients.

Amyloid nanofibrils are long and thin strands with cross β structures associated by hydrogen bonds. These structures can be formed under suitable conditions commonly at low pH and high temperatures. Fibrillated pinto bean protein isolate (FPBPI) was made by heating pinto bean protein at 85°C in an acidic condition while gently stirring at initial protein solution concentrations of 4 mg/mL, 13 mg/mL, and 21 mg/mL. Freeze-dried FPBPI's physicochemical, structural, and thermal characteristics were assessed, and they were compared with a native pinto bean protein isolate (PBPI) as a control. An increase in Congo red spectral absorption at 544 nm was observed following the fibril formation process. The largest concentration of freeze-dried fibrillated protein exhibited the highest Congo red spectral absorption. Fibrillar proteins' Fourier transform infrared (FTIR) spectrograms with lower wave numbers were seen than the native protein. For native PBPI, transmission electron microscopy (TEM) images were globular in shape, but they changed to long and curly morphologies in fibrillated proteins. FPBPI has a lower melting enthalpy than native protein when measured by differential scanning calorimetry (DSC). With the rising initial protein content, the enthalpy rose. Concurrently, semicrystalline structure for native and fibrillated pinto bean proteins was revealed by X-ray diffraction (XRD) findings. As the original protein concentration grew, so did the crystallinity intensity. Water-holding capacity (WHC) and oil-holding capacity (OHC) of freeze-dried FPBPI were higher than those of native protein. So, fibrillation of pinto bean protein helped it to serve as a good thickener in food industries.

Based on the effectiveness, measurability, and traceability of the quality marker (Q-marker) theory of traditional Chinese medicine, the Q-marker of Lycii Cortex (LC) was preliminarily predicted and analyzed. A UPLC-Q-TOF-MS qualitative analysis method for LC samples was established. A total of 44 LC chemical components, 16 plasma prototype components, 25 urine prototype components, and 27 fecal prototype components were identified. At the same time, the "component-target-disease" network diagram was constructed by network pharmacology to predict the potential active components of LC. A UPLC-MS/MS quantitative analysis method was established to determine the contents of 11 components such as kukoamine A in 35 batches of LC from seven producing areas. Principal component analysis, orthogonal partial least squares discriminant analysis, and other mathematical analysis methods were used to screen the differential components. Based on the comprehensive consideration of the Q-marker traceability, transitivity, specificity, effectiveness, and measurability, kukoamine A and kukoamine B were preliminarily predicted as LC potential Q-markers, and the high-quality producing area was determined to be Chengcheng County, Weinan City, Shaanxi Province. The prediction analysis of the LC Q-marker provides a reference for the comprehensive control of the quality of LC medicinal materials and also lays a foundation for the research and exploration of the substance basis and mechanism of action of LC.

Herein, a micro-solid-phase extraction (μSPE) method was developed using a pipette tip for rutin extraction, employing activated hollow carbon nanospheres (HCNSs) as the sorbent. Characterization of the activated carbon nanospheres through TGA, FTIR, and SEM analysis confirmed the success of the activation process. The study demonstrated the efficacy of PT-μSPE in rutin extraction under pH 2 conditions with a standard concentration of 2 mg·L^-1. The optimal mass of HCNSs was found to be 2 mg, and a loading volume of 500 μL resulted in the maximum recovery of rutin. Propan-2-ol was the best elution solvent with 15 aspirating/dispensing cycles. The correlation of determination (R ²) for the calibration curve was found to be 0.9991, and the LOD and LOQ values were 0.604 and 1.830 mg·L^-1, respectively. The applicability of the method was demonstrated by extracting rutin from a complex Moringa oleifera leaf extract with the relative standard deviation (RSD) of 3.26%, thereby validating this method as feasible for the extraction of useful bioactive compounds from complex plant samples.