Multiple target fishing hook prepared by photochemically coupling molecules in medicines onto magnetic nanoparticles / 中草药

Objective: To achieve multiple target fishing hook by efficiently grafting polymers containing benzophenone (BP) groups and photochemically coupling molecules in medicines onto magnetic nanoparticles (MNPs). Methods: MNPs attached carbonyl groups (Fe3O4-COOH) were prepared through a hydrothermal process. Then they were modified with DMSA, forming MNPs with thiol groups (Fe3O4-SH). Fe3O4-SH nanoparticles were grafted with polymer containing BP groups by surface-initiated condensation polymerization. Effects of monomer feed ratios and contents on the amounts of BP groups were investigated. The molecules in medicines were covalently coupled onto MNPs via photochemical reactions of BP groups. The contents of coupled molecules were determined by FT-IR and UV-Vis spectra analyses. Results: MNPs with average size of 100 nm were produced, modified with DMSA, and decorated by grafting polymer containing photosensitive BP groups. When the content of monomer containing BP groups was increased in grafting polymerizations, more BP groups were incorporated onto MNPs. This was conductive to the subsequent photo- coupling. FT-IR and UV-Vis spectra analyses confirmed the coupling of molecules in medicines. The active H and steric hinderance of the molecules affected their coupling. Conclusion: The resultant magnetic target fishing hook is ready as a probe for targets identification of traditional Chinese medicine (TCM).

Green, Low-cost Ball Milling-Hydrothermal Synthesis ofGraphene Quantum Dots and Applications / 分析化学

A ball milling method which is green with simple-manipulation and low-cost was used to prepare graphene as precursor for graphene quantum dots (GQDs) synthesis.Subsequently, GQDs with good dispersibility, uniform size distribution, average diameter of (4.80 ± 0.20) nm and 1-3 layers were prepared by one-step hydrothermal method.The morphology, structure and optical properties of the GQDs were characterized by high-resolution transmission electron microscopy (HRTEM), atomic force microscope (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), UV-Vis absorption and fluorescence spectroscopy.Furthermore, the GQDs were used in label-free and specific detection of ferric ion (Fe.3+) with broad linear ranges of 2.0×10.-6-7.0×10.-4 mol/L and low detection limit of 1.8 × 10.6 mol/L (S/N=3).The possible mechanism was also discussed and the application of GQDs for Fe.3+ detection in tap water was demonstrated.Finally, based on their low cytotoxicity and excellent biocompatibility, the as-prepared GQDs were successfully applied to efficient cell imaging.This work provides a new way for preparation of carbon-based nanomaterials and build a foundation for deepening applications of GQDs in bio-/chem-analysis, bioimaging, etc.

Synthesis of Novel Water-Soluble Silicon Quantum Dots with Imidazole Groups and Its Application in Fluorescent Detection of / 分析化学

Silicon quantum dot has become an attractive nanomaterial due to their excellent biocompatibility and optical performance. However, poor water-solubility of the traditional silicon quantum dot limits its wide application. In this study, we reported the synthesis of water-soluble silicon quantum dots with imidazole groups by using hydrothermal method, in which N-trimethysilylimidazole was used as a precursor of silicon. Compared with sodium borohydride, ascorbic acid, bovine serum protein, cysteine and citric acid, the as-prepared silicon quantum dots offered the strongest fluorescence intensity when sodium citrate was used as the reducing agent and stabilizer for the synthesis. The reaction could complete within 2 h at 220℃. The obtained silicon quantum dots showed good water-solubility with an average particle size of 2. 6 nm, and the result of infrared spectroscopic analysis verified the existence of free imidazole groups on the surface. By means of the investigation of the fluorescence quenching behavior of copper ions towards the silicon quantum dots at different temperatures, we found that the degree of fluorescence quenching increased with the increase of temperature. There results proved that the fluorescence decrease belongs to static quenching. Namely, the interaction of Cu2+ with imidazole groups on the surface of silicon quantum dots formed stable complex. In addition, the resonance light scattering analysis also showed that the fluorescence quenching process was accompanied by the agglomeration of particles. Based on the fluorescence quenching behavior of silicon quantum dots, we established a method for the fluorescent detection of Cu2+. When the concentration of Cu2+was in the range of 0. 04-2400 μmol/L, the fluorescence intensity would linearly decrease with the increase of Cu2+ concentration, and the detection limit (S/N=3) reached 1. 29×10-8 mol/L. The method provided high sensitivity, selectivity and reproducibility, and was successfully applied to the determination of trace copper in fruits and vegetables.

Preparation of hydroxyapatite in the presence of amino acids by hydrothermal method / 国际生物医学工程杂志

Objective To investigate the preparation method of hydroxyapatite by amino acids induced hydrothermal technique.Methods The hydroxyapatite nanorods were obtained using alanine and glycine as templates by hydrothermal method.The samples were characterized by X-ray diffraction (XRD),Fourier infrared spectroscopy (FTIR),transmission electron microscopy (TEM).Results The results showed that amino acids induced the formation of hydroxyapatite.Amino acids could affect crystallinity and dispersion of the formed hydroxyapatite.In addition,the substituent content of carbonate ions in hydroxyapatite was reduced by changing the ratio of amino acids.Conclusion Hydroxyapatite with high crystallinity and low carbonate ions can be prepared by hydrothermal method in the presence of amino acids.

Preparation of TiO2 Nano-materials and Photocatalytic Purification of Sewage / 环境与健康杂志

The recent research progress of photo-catalyzed degradation of organic pollutants by TiO2 is reviewed,the characteristics of hydrothermal method and the prepared processes of TiO2 were discussed,the photo-catalyzed mechanism under UV and visible light and the application of degradation of sewage using TiO2 nanomaterials from five aspects were described in this paper. The main problems existing in the studies of TiO2,the research directions,and the development prospects were also discussed.

Surface characteristics and biological responses of hydroxyapatite coating on titanium by hydrothermal method: an in vitro study / 대한치과보철학회지

STATEMENT OF PROBLEM: Hydroxyapatite(HA) coated titanium surfaces have not yet showed the reliable osseointegration in various conditions. PURPOSE: This study was aimed to investigate microstructures, chemical composition, and surface roughness of the surface coated by the hydrothermal method and to evaluate the effect of hydrothermal coating on the cell attachment, as well as cell proliferation. MATERIAL AND METHODS: Commercially pure(c.p.) titanium discs were used as substrates. The HA coating on c.p. titanium discs by hydrothermal method was performed in 0.12M HCl solution mixed with HA(group I) and 0.1M NaOH solution mixed with HA(group II). GroupI was heated at 180degrees C for 24, 48, and 72 hours. GroupII was heated at 180degrees C for 12, 24, and 36 hours. And the treated surfaces were evaluated by Scanning electron microscopy(SEM), Energy dispersive X-rayspectroscopy(EDS), X-ray photoelectron spectroscopy(XPS), X-ray diffraction method(XRD), Confocal laser scanning microscopy(CLSM). And SEM of fibroblast and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) assay were used for cellular responses of the treated surfaces. RESULTS: The color of surface changed in both groups after the hydrothermal process. SEM images showed that coating pattern was homogeneous in group II, while inhomogeneous in group I. H72 had rosette-like precipitates. The crystalline structure grew gradually in group II, according to extending treatment period. The long needle-like crystals were prominent in N36. Calcium(Ca) and phosphorus(P) were not detected in H24 and H48 in EDS. In all specimens of group II and H72, Ca was found. Ca and P were identified in all treated groups through the analysis of XPS, but they were amorphous. Surface roughness did not increase in both groups after hydrothermal treatment. The values of surface roughness were not significantly different between groups I and II. According to the SEM images of fibroblasts, cell attachments were oriented and spread well in both treated groups, while they were not in the control group. However, no substantial amount of difference was found between groups I and II. CONCLUSIONS: In this study during the hydrothermal process procedure, coating characteristics, including the HA precipitates, crystal growth, and crystalline phases, were more satisfactory in NaOH treated group than in HCl treated group. Still, the biological responses of the modified surface by this method were not fully understood for the two tested groups did not differ significantly. Therefore, more continuous research on the relationship between the surface features and cellular responses seems to be in need.