Hue University Journal of Science: Natural Science

Synthesis of Cu- and Ag-modified flower-like Ni(OH)₂ nanocomposites

Hung Sinh Vu — 2025-12-24

In this report, a simple template-free hydrothermal method was used to synthesize flower-like Ni(OH)₂ structures modified with Ag and Cu. The Ni(OH)₂ microflowers were formed via the self-assembly of ultrathin nanosheets with a thickness of approximately 2–3 nm. The incorporation of Ag and Cu at appropriate concentrations preserved the three-dimensional flower-like architecture of Ni(OH)₂. For the Ag–Ni(OH)₂ composite, Ag nanoparticles were uniformly dispersed on the Ni(OH)₂ nanosheets. In contrast, no Cu(OH)₂ phase was detected in the Cu–Ni(OH)₂ composite, likely due to Cu substituting for Ni sites within the Ni(OH)₂ lattice. Owing to the unique three-dimensional (3D) flower-like structure, high specific surface area, and the enhanced physicochemical properties introduced by metal modification, these materials can be potential for applications in electrochemical sensing, catalysis, and biomedical fields.

Green-Synthesized NiFe₂O₄-CQDs Composite for Sensitive Electrochemical Detection of Acetaminophen and Caffeine

Chau Ngoc Anh Vo — 2025-12-24

In this study, a NiFe₂O₄-CQDs composite was synthesized and utilized to modify a glassy carbon electrode (GCE) for the simultaneous electrochemical detection of acetaminophen (ACP) and caffeine (CFE). The composite material was characterized using various techniques, including FTIR and PL spectroscopy, confirming its suitability for electrochemical applications. The DP-ASV method was employed to determine the limit of detection (LOD) for ACP and CFE, which were found to be 0.35 μM and 0.34 μM, respectively. The electrochemical method exhibited a wide linear range from 0.5 μM to 11.9 μM for both analytes. Optimized experimental conditions, including accumulation potential, accumulation time, and pulse amplitude, contributed to high sensitivity, reproducibility, and accuracy in detecting these compounds. Recovery studies in pharmaceutical samples demonstrated reliable results, with recoveries ranging from 94.2% to 103.2%. These findings suggest that the NIF-CQDs-modified GCE is a promising candidate for rapid and accurate electrochemical analysis of ACP and CFE in real-world applications.

An in silico study on the anti-diabetic potential of some compounds from the genus Cordyceps

Đại Châu Nguyễn — 2025-12-24

Abstract
This study was designed to evaluate the inhibitory potential of nine representative compounds, belonging to the nucleoside, flavonoid, and steroid classes from Cordyceps species, against two protein targets: α-amylase (PDB ID: 4W93) and α-glucosidase (PDB ID: 3W37) using an in-silico approach. Molecular docking simulations identified sites 1 and 2 as the optimal sites for ligand interaction with the two respective proteins. The docking’s results were validated, with RMSD values for all complexes less than 2.0 Å and compound C3 was identified as the most potent inhibitor for protein 4W93, while C2 was the most effective against protein 3W37. According to Lipinski's rule of five indicated that all compounds (C1-C9) exhibit favorable "drug-likeness" characteristics and the pharmacokinetic and toxicological properties of these compounds were further evaluated via ADMET parameter predictions. The complexes, C3-4W93 and C2-3W37, were selected for molecular dynamics (MD) simulations, which demonstrated that both complexes are structurally stable throughout the simulation; of these, the C3 ligand was observed to form the most favorable and persistent interactions with the 4W93 protein.

Free amino acid production in response to selenium nanoparticles in rice plants

Nga T.P. MAI — 2025-12-24

Rice (Oryza sativa L.) is the main food source for nearly half of the world's population. Selenium nanoparticles (SeNPs) have emerged as potential agents in plant sciencedue to their ability to mitigate biotic and abiotic stresses, and increase plant productivity. Free amino acids (FAA) are key metabolites involved in plant stress responses and homeostatic regulation. The present study investigated the FAA profiles in response to SeNP treatment which ranged from 0 -to25 ppm in two-week-old rice plants. The concentration of FAA was determined by using high-performance liquid chromatography. Results demonstrated a dose-dependent increase in FAA accumulation, with the highest concentration (25 ppm SeNPs) leading to maximum FAA content in shoots (approximately 33 mg/g dry weight), compared to roots (11–13 mg/g). Moreover, increased concentration of SeNPs stimulated more total FAA production. The aspartate family contributed the largest fraction of total FAA, comprisingapproximately 50% under 25 ppm treatment. Additionally, essential amino acid levels significantly increased with higher SeNP concentrations, reaching approximately 23 mg/g in shoots at 25 ppm. The accumulation of lysine, threonine, and serine was notably enhanced in response to SeNP treatment, suggesting their involvement in protective or compensatory metabolic pathways under stress conditions. Among these, lysine exhibited the highest level of accumulation, indicating a potentially prominent role in the plant's adaptive response to SeNP-induced stress. These findings highlight SeNP-induced modulation of FAA metabolism in rice and suggest a potential mechanism for enhancing stress resilience through targeted amino acid biosynthesis.

Characterization of Vibrio spp. Isolated from Shrimp Pond Water in Hue City, Vietnam

Thi Kim Co Nguyen — 2025-12-24

This study investigates the characteristics of Vibrio strains isolated from shrimp pond water in Hue City, focusing on their biochemical properties, antibiotic resistance, extracellular enzyme production, hemolytic activity, and toxin-encoding genes. Five Gram-negative, oxidase, and catalase-positive, motile bacterial strains forming colonies on TCBS and CHROMagar™ Vibrio were selected and designated as V06, V16, V17, V25, and V29. Analysis of their 16S rRNA sequences revealed 98.78% to 99.99% similarity with four Vibrio species: V. parahaemolyticus, V. alginolyticus, V. azureus, and V. sinaloensis. All isolates exhibited multidrug resistance to at least four antibiotics. Notably, all strains showed 100% resistance to vancomycin, penicillin, and ampicillin. Hemolytic activity varied among the strains in which V06 displayed beta-hemolysis, V17, and V29 showed alpha-hemolysis, while V16 and V25 exhibited indeterminate hemolytic activity on blood agar. Additionally, all strains demonstrated the ability to produce extracellular proteases and lipases, which have been formerly demonstrated to be related to virulence in Vibrio species. Molecular analysis revealed the presence of toxR and tlh genes in all strains; however, no trh, tdh, pirA, or pirB genes were detected. These findings suggested that the isolated Vibrio strains possessed many virulence-associated traits, including enzyme production, toxR and tlh genes presence, hemolytic activity, and significant antibiotic resistance, which may enhance their pathogenic potential in aquaculture environments.

Malnutrition Status and the Impact of Daily Activities and Dietary Habits on Stunting: A Study of 4,871 Preschool Children in Inner-City Hanoi

Thi Tuyet Le — 2025-12-24

This study aimed to investigate malnutrition and the impact of daily activities and dietary habits on stunting in preschool children to identify effective prevention strategies. The study included two phases: a cross-sectional analysis of 4,871 children from nine preschools in Hoang Mai district and a case-control study of 207 stunted children and 2,984 normal-height children , using WHO criteria for nutritional status classification. Results indicated that the prevalence of underweight, stunting, and wasting was 3.6%, 7%, and 2.4%, respectively. Underweight and stunting were more common among girls (4.4% vs. 3.0% and 8% vs. 6%, respectively), while wasting was slightly higher in boys (2.5% vs. 2.2%). Significant associations with stunting included less than 1 hour of moderate and vigorous physical activity (Odds Ratio (OR) = 1.71) and meal times exceeding 40 minutes (OR = 1.73). Preferring to eat lean meat reduced the risk of stunting (OR = 0.72, 95% Confidence Interval (CI) = 0.54–0.98). Factors such as night sleep duration, bedtime, active physical activities at school, sedentary behaviors, and preferences for fats, sweets, eggs, vegetables, and milk consumption before sleep were not significantly associated with stunting. The study suggests that monitoring eating times, encouraging more moderate and vigorous physical activity, and increasing lean meat consumption can help reduce the risk of stunting in children.

Determination of the dead time of the TCS-172 gamma survey meter using the two source method

Dang Quyet Pham — 2025-12-24

Dead time is one of several major parameters of a nuclear radiation measurement system. To estimate the dead time and its uncertainty for the TCS-172 gamma survey meter at the Training Center of the Nuclear Research Institute, 240 count rate measurements were carried out using the two-source method with the non-paralyzable model and two standard radioactive sources, Cs-137 and Co-60. The results indicate that the dead time for this instrument was found to be 11.29 µs, with an uncertainty of ± 1.6 µs. These values show strong agreement with those found in the textbook and several articles.

Existence and linear conditioning for solutions of equilibrium problems in metric spaces

Thi Nhu Bich Le — 2025-12-24

In this paper, we provide sufficient conditions for the existence and linear conditioning of equilibrium problems in metric spaces. Our results improve and generalize some well-known results in the literature.