Journal of Nanoparticle Research最新文献

Carbon quantum dots (CQDs) and Nitrogen-doped CQDs (N-CQDs) were synthesized through a one-step hydrothermal process, utilizing reed leaves and urea as carbon and nitrogen sources, respectively. The maximum excitation wavelength of CQDs and N2-CQDs was 325 nm, and the corresponding emission wavelength was 407 nm and 406 nm, respectively. Synthetic CQDs have excellent fluorescence properties, while N-doping enhances the fluorescence intensity and stability of CQDs. Next, the adsorption effect of N2-CQDs on various metal ions was also studied using the fluorescence quenching method. The results showed that N2-CQDs have a significant capacity for adsorption of Cu²⁺ ions. The following quantitative analysis indicated that the Cu²⁺ concentration showed an excellent linear relationship between 0~500 μmol/L and the limit of detection (LOD) was 0.074 μmol/L. The N2-CQDs at 0-200 μg/mL have no deleterious effects on the viability of HeLa cells and the survival rate of Artemia nauplii. Finally, the agarose gel containing N2-CQDs was constructed, and its absorption behavior of Cu²⁺ in artificial seawater was evaluated. The results showed that this N2-CQDs-based gel was able to efficiently remove Cu²⁺ from seawater, leading to a higher survival rate of the nauplii under 10 and 50 mg/L Cu²⁺ stress. Our results collectively provide a cost-effective method for removing heavy metal ions from seawater and mitigating their harmful effects on sea animals.

Ciprofloxacin is a fluoroquinolone group antibiotic used to treat variety of bacterial illnesses. The purpose of this study is to develop a rapid and accurate spectrophotometric approach for the detection of ciprofloxacin using gold nanoparticles (GNPs). Localized surface plasmon resonance (LSPR) absorption band of GNPs at 523.0 nm was utilized as the spectrophotometric detection of ciprofloxacin. To determine the optimum GNPs concentration and pH value of the phosphate buffer solution used in the experimental research, the effect of pH values and GNPs concentrations in the absorbance value of ciprofloxacin-GNPs was investigated. The linear operating range for the developed spectrophotometric method was 0.015–1.48 µg/mL in pH 7.0 phosphate buffer solution. In the recovery study conducted to detect the amount of ciprofloxacin in commercial ear drops, the recovery value was calculated as 91.06 ± 1.21%.

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This study proposed a treatment strategy based on the application of poly(vinyl alcohol)-based magnetic hydrogel (PVA-MH) beads for the adsorptive removal of cadmium from synthetic domestic wastewater. The hydrogels were prepared through a facile and rapid synthesis procedure and used to remove cadmium ions from domestic wastewater. The influential parameters of adsorption process were studied by varying the type and volume of buffer solution, mass of adsorbent, and shaking period. The optimum parameters of the adsorption process were found as 1.0 mL of pH 8.0 buffer solution, 100 mg of PVA-MH beads, and 30 min orbital shaking. The process of adsorption equilibrium was clarified by the three-parameter Sips model, and outcomes indicated that this model, with an R² value of 0.9876, fitted the experimental data effectively. Moreover, sorption kinetic results are well described by the pseudo-second-order kinetic model. The findings indicated that both monolayer adsorption and multi-site interactions governed the adsorption of cadmium onto the hydrogel surface and the swelling characteristics of PVA-MH beads had a low influence on the adsorption mechanism.