Minrui Ou

Encapsulating Fe3O4 into calcium alginate coated chitosan hydrochloride hydrogel beads for removal of Cu (II) and U (VI) from aqueous solutions

The aim of this work was to study the removal of Cu (II) and U (VI) ions from aqueous solutions by encapsulating magnetic Fe3O4 nanoparticles into calcium alginate coated chitosan hydrochloride (CCM) hydrogel beads. ATR-FTIR and XRD analysis data indicated that the CCM composites were successfully prepared. SEM images and EDX spectra showed that Cu2+ and UO22+ ions were adhered onto sorbents. Adsorption properties for removal of both copper and uranium ions under various experimental conditions were investigated. Kinetic data and sorption equilibrium isotherms were also conducted in batch process. The sorption kinetic analysis revealed that sorption of Cu (II) and U (VI) followed the pseudo-second-order model well and exhibited 3-stage intraparticle diffusion model during the whole sorption process. Equilibrium data were best described by Langmuir model, and the CCM composite hydrogel beads showed the estimated maximum adsorption capacity 143.276mg/g and 392.692mg/g for Cu (II) and U (VI), respectively. The CCM adsorbent exhibited excellent reusability for five cycles use without significant changes in the adsorption capacity and structural stability. The results demonstrated that CCM can be an effective and promising sorbent for Cu (II) and U (VI) ions in wastewater.

Oxidative removal of phenol by HRP-immobilized beads and its environmental toxicology assessment.

Horseradish peroxidase shows potential biological and environmental applications on the removal of phenolic compounds. In the present study, the HRP-immobilized beads were synthesized to detect the efficiency of the removal of phenol at optimum pH and H2O2 concentration. Comparative in vitro cytotoxicity of phenol/treated solutions were evaluated in HeLa, HepG2 and mcf-7 cells by using MTT method along with flow cytometry study for cell viability and cell cycle distributions. The results showed that the toxicity of phenol solutions were greatly reduced after treated by HRP-immobilized beads, and phenol could lead to deactivate of cells in the S phase and preventing them from going into the G2/M checkpoint. In addition, molecular docking study showed that phenol was a valid inhibitor for the cyclin E in the cell cycle and cell metabolism. Thereby, we established a suitable strategy with promising application for efficient harmless removal of phenol, which significantly decreased the cytotoxic impacts of phenol.

First report on a BODIPY-based fluorescent probe for sensitive detection of oxytetracycline: application for the rapid determination of oxytetracycline in milk, honey and pork

A new BODIPY-based fluorescent probe (S) for oxytetracycline bearing hydrophilic carboxyl has been designed and synthesized. Fluorescence is quenched by oxytetracycline (OTC), and the effect was used to develop a method for the determination of OTC. This is the first report on the determination of OTC by a BODIPY-based “turn-off” fluorescence probe, which provides a sensitive and selective method for OTC detection. S exhibited higher properties, such as acting as a “naked eye” probe, stronger anti-jamming capability, outstanding thermal stability, good stability to pH, fast-response characteristics, and better live-cells imaging with low cytotoxicity when compared with other probes. Moreover, this is the first time that one chemosensor could be successfully applied to OTC imaging in zebrafish, which demonstrated its excellent organism permeability. Furthermore, the feasibility of the developed assays in milk, honey, and pork samples was verified through recovery experiments using spiked samples. Under the optimum conditions, good linearity was obtained in the range of 0–42 µM and the recoveries ranged from 101.3% to 104.8%, 101.9% to 107.9%, and 98.3% to 109.5% for milk, honey, and pork, respectively, with relative standard deviations less than 1.74%.

Graphene oxide encapsulated polyvinyl alcohol/sodium alginate hydrogel microspheres for Cu (II) and U (VI) removal

In this work, a novel sodium alginate (SA)/polyvinyl alcohol (PVA)/graphene oxide (GO) hydrogel microspheres were prepared by a simple method. Sodium alginate was physically crosslinked by Ca2+; GO was encapsulated into the composite to strengthen the hydrogels; PVA played a significant role in well dispersing of GO in SA. The SA/PVA/GO (SPG) hydrogels were employed as an efficient adsorbent for removal of Cu (II) and U (VI) from aqueous solution. Batch experiments with the subject of the pH, initial metal ion concentration, competing ions and contact time were investigated. Structure characterization was successfully conducted by FTIR, SEM, EDX, BET and XPS. Furthermore, the sorption kinetics of Cu2+ and UO22+ followed pseudo-second order model and exhibited 3-stage intraparticle diffusion model. Equilibrium data were best described by Langmuir model and the obtained maximum adsorption capacities of SPG hydrogel microspheres for Cu2+ and UO22+ were 247.16 and 403.78 mg/g, respectively. The difference in adsorption capacity can be confirmed by the percentage of elements in EDX spectra and the intension of peak of elements in XPS spectra. The SPG sorbent exhibited excellent reusability after 5 adsorption-desorption cycles. All results suggested that the prepared adsorbents could be considered as effective and promising materials for removal of Cu (II) and U (VI) in wastewater.

Development of a Novel Mixed Titanium, Silver Oxide Polyacrylonitrile Nanofiber as a Superior Adsorbent and its Application for MB Removal in Wastewater Treatment

In this study, a novel electrospun nanofibrous composite was synthesized from polyacrylonitrile (PAN) and well-dispersed oxide nanoparticles containing Ti and Ag (PAN-TA). The nanoparticles incorporated into the nanofibers can endow the composite with photocatalytic and antimicrobial ability. The morphologies and structure of the nanofibers were characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Controlled experiments were carried out with the effects of chemical modification, solution pH, temperature, dosage, contact time, and initial concentration of the dye. The methylene blue (MB) dye was completely removed within 20 min at room temperature 25 oC with high maximum retention capacity of 155.4 mg g. Moreover, equilibrium data and kinetics data indicated that the dye adsorption agreed well with the Langmuir isotherm model and pseudo-second order model, respectively. In addition, the nanofibers could be easily separated from dye solution and showed high reusability for numerous repeat cycles, thus indicating good application prospects for the wastewater treatment.

Development of a Novel Spectrophotometric Method Based on Diazotization- Coupling Reaction for Determination of Bisphenol A

Bisphenol A (BPA) is an industrial material which can lead to endocrine disorders. In this work, a simple and sensitive spectrophotometric method for determination of BPA using diazotizationcoupling reaction was presented. To achieve the best performance of the developed method, the experimental parameters were optimized in terms of reagent concentration, reaction time, pH, and temperature. Under the optimal conditions, the absorbance increased linearly with the increasing concentration of BPA in the range of 0.16-10.4 μg mL with the correlation coefficient of 0.9991 and the detection limit of 0.05 μg mL. Results achieved with the spectrophotometric method were compared with those obtained using high performance liquid chromatography (HPLC) method. The proposed method was successfully applied to determine BPA in milk and water bottle samples and satisfactory results were obtained, which make it very suitable for routine analysis of BPA in quality control laboratories.