Publications by authors named "Ngoc Van Thi Nguyen"

Article Synopsis
  • The AgNPs-Alg-Chi nanocomposite film shows strong antibacterial effects against pure bacterial strains and those from acne patients, but its cytotoxicity needs more exploration at higher silver doses.* -
  • The films were made using eco-friendly methods, featuring kumquat extract to reduce silver ions, and were characterized through various advanced techniques.* -
  • Results indicate that the films have comparable antibacterial potency to solutions of silver nanoparticles while maintaining over 70% cell viability in human keratinocytes, suggesting they are safe for potential human applications.*
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The development of nanocomposite photocatalysts with high photocatalytic activity, cost-effectiveness, a simple preparation process, and scalability for practical applications is of great interest. In this study, nanocomposites of TiO Degussa P25 nanoparticles/activated carbon (TiO/AC) were prepared at various mass ratios of (4:1), (3:2), (2:3), and (1:4) by a facile process involving manual mechanical pounding, ultrasonic-assisted mixing in an ethanol solution, paper filtration, and mild thermal annealing. The characterization methods included XRD, SEM-EDS, Raman, FTIR, XPS, and UV-Vis spectroscopies.

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Linagliptin is a highly specific, long-acting inhibitor that is used as an orally administrable agent for type-2 diabetes treatment. Because only the R-enantiomer is of clinical use, we developed a capillary electrophoresis method for the determination of the enantiomeric impurity of this compound. Carboxymethyl-β-cyclodextrin was selected as the chiral selector for the separation of linagliptin enantiomers.

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Capillary zone electrophoresis was successfully applied to the enantiomeric purity determination of valsartan using acetyl-β-cyclodextrin (A-β-CD) as a chiral selector. Separations were carried out in a 50 µm, 64/56 cm fused-silica capillary. The optimized conditions included 25 mM phosphate buffer, pH 8.

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A rapid, simple and sensitive chiral HPLC method was developed and validated for quantification of biologically important alkaloids namely evodiamine enantiomers and rutaecarpine in Evodiae fructus using diphenhydramine as the internal standard (IS). Chromatographic separations were performed on a Chiralpak AD-H column (250 mm × 4.6 mm i.

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Capillary electrophoresis (CE) and proton nuclear magnetic resonance spectroscopy ((1)H-NMR) have been used to discriminate the enantiomers of sibutramine using cyclodextrin derivatives. Possible correlation between CE and (1)H-NMR was examined. Good correlation between the (1)H-NMR shift non-equivalence data for sibutramine and the degree of enantioseparation in CE was observed.

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Stereoisomers of nadolol were derivatized with S-(-)-menthyl chloroformate((-)-MCF) forming their diastereomers, RSR-nadolol-(-)-MCF, SRS-nadolol-(-)-MCF, RRS-nadolol-(-)-MCF and SSRnadolol-(-)-MCF. Diastereomeric mixture were then chromatographically resolved by preparative HPLC (JAIGEL-ODS-BP-L, 500 × 25 mm column) eluted with methanol-water (84:16, v/v) at flow rate 2.5 mL/min.

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