BMC Chemistry最新文献

Water contaminated with heavy metal ions poses serious threat to the human health and environment protection. It is imperative to develop analytical tools to detect heavy metal ions. Herein, we propose autofluorescence free SiO₂ modified upconversion nanosensor for label-free and fast determination of MnO₄⁻ and Cr₂O₇²⁻ anions. The highly efficient and multi-colour upconversion luminescence (UCL) of UCNPs@SiO₂ was effectively quenched by MnO₄⁻ and Cr₂O₇²⁻ anions with fast response time of 2 and 1 min, respectively. The UCNPs@SiO₂ nanosensor exhibits linear detection ranges of 0.6–2000, 2–2000 µM with the LOD at 0.15, 0.04 µM for MnO₄⁻ and Cr₂O₇²⁻ anions, respectively. The nanosensor was successfully applied for real lake and tap water samples with satisfactory results. The UCNPs@SiO₂ UCL nanosensor demonstrates autofluorescence free and fast determination of MnO₄⁻ and Cr₂O₇²⁻ anions with high sensitivity, good specificity, low LOD, and wide linear detection range, holding great potential for food and environmental sample sensing.

The increasing prevalence of toxic elements such as nickel (Ni) in the environment poses a significant threat to human health due to its carcinogenic effect. The study investigates the Ni biosorption potential of three cyanobacteria strains: Euhalothece sp., Halospira sp., and Chroococcidiopsis sp. Hence, the physicochemical properties of biomass and extract were assessed through transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and Brunauer-Emmet-Teller (BET). Batch experiments for Ni²⁺ biosorption were conducted and residual nickel (Ni²⁺) levels were quantitatively assessed using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The results evidence interesting Ni²⁺ removal efficiency of Chroococcidiopsis sp. biomass reaching a biosorption capacity of 18.19 mg g⁻¹ under pH 6, and 37 °C. Several functional groups including amide, carbonyl, phosphate, and carboxyl groups were revealed as key players in this process via FTIR. Finally, such findings highlight the significant potential of cyanobacterial biomass and by-products to reduce nickel bioavailability to prevent Ni-induced carcinogenesis.

Graphical Abstract

A new combination of silodosin and mirabegron has recently obtained approval in the Indian market for addressing the benign prostatic hyperplasia symptoms associated with overactive bladder syndrome. In this study, we present four validated UV-spectrophotometric methods that rely on straightforward mathematical calculations for the quick and simultaneous assay of MRB and SLD in commercial tablets and synthetic mixes without the need for prior separation. The suggested methods include dual-wavelength, induced dual-wavelength, ratio difference, and area under the curve. These methods were effectively used to determine SLD and MRB simultaneously in combinations with severe spectrum overlap, showing excellent recoveries free from interference from pharmaceutical excipients. The proposed approaches were assessed and validated following the guidelines set forth by the International Conference for Harmonization (ICH). The methods exhibited linear ranges of 1–20 μg mL⁻¹ and 1–25 μg mL⁻¹ for SLD and MRB, respectively. Their environmental friendliness was assessed using the Analytical Greenness Calculator (AGREE) and The Green Analytical Procedure Index (GAPI) tools, demonstrating their supremacy in terms of greenness compared to the reported chromatographic method. There were no appreciable variations in accuracy or precision between the reported chromatographic method and statistical comparisons based on t- and F values. Consequently, these suggested methods are deemed effective in routine analysis of SLD and MRB, serving as cost-effective alternatives in quality control laboratories lacking expensive chromatographic instruments.

In this study, a new nanocomposite comprising 4-(2-Aminoethyl)-morpholine, an organic catalyst, was prepared on the surface of silica. The absence of metal in the catalyst structure contributes to its environmental friendliness. This novel nanocatalyst was used for multi-component reactions (MCRs). Having a nano size for the composite enhances the contact between the raw materials and the catalytic surface, leading to significant advancement in the reaction. The synthesized composite was identified and evaluated using FT-IR, EDX, EDX-Mapping, TGA, XRD, BET, TEM, and FE-SEM analysis. The characteristic analysis confirmed the synthesis of both nano-silica/4-(2-Aminoethyl)-morpholine catalyst and polyhydroquinoline. The composite’s catalytic properties for synthesizing some polyhydroquinoline derivatives were investigated, yielding promising and remarkable results with high 95% yields and short reaction times. The antibacterial properties of the synthesized compounds were also examined against four types of pathogenic bacteria. The highest inhibitory effect was attributed to the compound Ethyl-4-(3-hydroxyphenyl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate exhibited the highest antibacterial properties.

Background

Pantoprazole (PAN) is a proton pump inhibitor used to treat GERD and hyperacidity by suppressing gastric acid secretion, effectively relieving symptoms such as heartburn, acid regurgitation, and indigestion. Domperidone (DOM) is a prokinetic agent that enhances gastrointestinal motility, helping to alleviate nausea, vomiting, and bloating caused by motility disorders. Their combination (Pantosec-D) provides rapid and comprehensive relief from both acid-related and motility-related symptoms, significantly improving patient comfort and quality of life.

Objective

This study aims to develop and validate three eco-friendly spectrophotometric techniques—ratio difference (RD), first derivative (1DD), and mean centering (MC) of ratio spectra—for the simultaneous determination of PAN and DOM in pharmaceutical formulations.

Method

The proposed methods resolve spectral overlap through ratio spectra manipulation. In the RD method, DOM is quantified by measuring the amplitude difference at 209 nm and 233 nm, while PAN is determined at 254 nm and 223 nm. The ¹DD method detects DOM at 215 nm and PAN at 249 nm, whereas the MC method quantifies PAN at 254 nm and DOM at 209 nm.

Results

The suggested methods were validated according to ICH regulations. Pharmaceutical formulations comprising PAN and DOM were effectively analyzed using the linear correlations obtained for both drugs over concentration ranges of 0.5–52 µg/mL and 1–18 µg/mL, respectively.

Conclusion

Compared with reported spectrophotometric techniques, ratio methods are especially beneficial for routine pharmaceutical analysis due to their ease of use, capacity for handling overlapping spectra, and robustness to experimental variations. Compared with reported chromatographic methods, these techniques provide easy-to-use, reasonably priced, less solvent, and dependable substitutes for the standard quality control of these medications in pharmaceutical dosage forms.

A novel sedative/hypnotic drug called suvorexant (SUV) is advised for treating insomnia. From a forensic standpoint, it is important medicine because of its sedative/hypnotic and depressing effects. There are no green “high-performance thin-layer chromatographic (HPTLC)” techniques for measuring SUV in the literature. Therefore, this study aims to develop and validate a reverse-phase HPTLC approach that indicates green stability for SUV measurement in commercially available tablet dosage forms. SUV was detected at 255 nm in wavelength. The suggested SUV analysis approach’s greenness was assessed using the “analytical eco-scale (AES), ChlorTox, and analytical GREEnness (AGREE)” tools. The current SUV analysis method showed linearity in the 10–1200 ng/band range. Furthermore, the SUV analytical method was robust, accurate (% recoveries = 98.18–99.30), sensitive (LOD = 3.32 ng/band and LOQ = 9.98 ng/band), precise (% CV = 0.78–0.94), and environmentally friendly. The “AES, total ChlorTox, and AGREE” scales were derived to be 93, 0.96 g, and 0.88, respectively, using the current SUV analytical method, demonstrating an exceptional greenness profile. SUV was shown to be suitably unstable under oxidative degradation conditions and suitably stable under acid, base, and heat degradation conditions. Furthermore, the SUV analytical method’s stability-indicating component identified SUV in the presence of its breakdown products. It was observed that marketed SUV tablet brands A and B contained, respectively, 98.18 and 101.32% of SUV. The findings of the study indicated that SUV in marketed tablet dosage forms may be monitored on a regular basis with the use of the current green HPTLC methodology.

Head and neck squamous cell carcinoma (HNSCC) is the most common head and neck cancer and highly aggressive and heterogeneous. Targeted therapy is still the main treatment method used in clinic due to lower side effect and personalized medication. In order to discover novel and effective drugs with low side effect against HNSCC, we analyzed the genes related to HNSCC, and found that PIK3CA was highly expressed in tumor tissues and often experienced mutations, leading to excessive activation of phosphoinositide 3-kinase alpha (PI3Kα), promoting the development of HNSCC. The allosteric PI3Kα inhibitor STX-478 inhibits the growth of tumor with hotspot mutations in PI3Kα and shows prominent efficacy on the treatment of human HNSCC xenografts without displaying the metabolic dysfunction observed in Alpelisib. These mutations open the allosteric site more readily, increasing the selectivity of STX-478 for mutant PI3Kα. STX-478 cleverly avoids the side effect of ATP competitive PI3Kα inhibitors. So, the structure of STX-478 was optimized based on the interaction mechanism between STX-478 and PI3Kα. Then, virtual screening, binding mode research, target verification, physical and chemical properties, pharmacokinetic properties and stabilities of ligand-PI3Kα complexes were evaluated by computer technologies (scaffold hopping, cdocker, SuperPred, SwissTarget prediction, Lipinski’s rule of five, ADMET and MD simulation). Finally, J-53 (2-oxopropyl urea compound) with excellent properties was selected. J-53 not only formed H-bonds with key amino acids, but its unique -C(O)CH₃ could also form H-bonds with ILE1019, making it more stably bound to PI3Kα and contributing to its activity. After the SciFinder verification, J-53 with novel structure had the value of further study. This study suggested that J-53 could be used as potential inhibitors of PI3Kα, and provides valuable information for the subsequent drug discovery of allosteric PI3Kα inhibitors.

Graphical Abstract

Carbon sequestration by application of organic materials and biochar in soil is an important strategy to increase soil organic carbon (SOC), but the stability of SOC, particularly humic substances (HS) vary with the types of organic material. In this study, cotton straw and its derived compost and biochar were added with equivalent carbon content to soil and incubated for 180 days. The structural characteristics of humic acid (HA), fulvic acid (FA) and humin (Hu) were investigated using solid-state ¹³C nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy. The results showed that biochar treatment increased the aryl C of HA, FA, and Hu by 1.38%, 1.68%, and 10.46% compared to straw treatment and increased the aryl C of HA, FA, and Hu by 1.46%, 1.99% and 2.01% compared to compost treatment. The O-alkyl C of HA was 10.59% and 10.65% in high biochar/straw and biochar/compost ratios respectively, while it was 9.81% and 9.61% in low biochar/straw and biochar/compost ratios. In addition, the O-alkyl C of FA was 62.83% and 58.48% in high ratios of biochar/straw and biochar/compost, respectively, while it was 55.85% and 55.94% in low ratios of biochar/straw and biochar/compost. These results suggest that biochar is advantageous for aryl C formation of FA and Hu due to its high aryl C content, whereas straw or compost is advantageous for alkyl C formation of HA. The stability of aryl C and O-alkyl C of HA, FA, and Hu can be improved in soils by incorporating biochar in combination with straw or compost.

Graphical abstract

Bone regeneration is one of the most effective methods for treating bone defects. In this work, tricarboxylic cellulose/sodium alginate loaded with hydroxyapatite (HA) and/or graphene oxide (GO) was coagulated by calcium ions to create beads as scaffolds. In the first, cellulose was oxidized to water-soluble tricarboxylic cellulose (TCC) by 2,2,6,6‐tetramethylpiperidine-1-oxyl (TEMPO), periodate, and chlorite oxidation. HA was extracted from eggshells via microwave treatment, and GO was synthesized using the Hummer method. The structural behavior of the formed beads was meticulously investigated through various characterization techniques such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The SEM images confirmed the formation of particles of micrometric size without any specific morphology. Incorporating GO or HA does not affect the morphologies of the materials on the micrometric scale. The cytocompatibility of different bead preparations was studied on murine mesenchymal stem cells. Moreover, the swellability in water and biodegradability by cellulase enzyme of prepared beads were studied. The results show that the prepared beads may be promising for bone tissue engineering.