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Methacrylated gelatin films with in situ-generated TiO 2 nanoparticles containing varying weight percentages of gelatin (0 %, 0.5 %, 1 %, 2 % and 4 %) were successfully prepared as novel biomaterials. 1 H-NMR spectroscopy confirmed their methacrylation with a 79 % degree of substitution. TiO 2 nanoparticles were uniformly distributed in the films with the average particle size increasing from 85 to 130 nm in proportion to an increase in TiO 2 concentration from 0.5 to 4 wt%. The water absorption of various gelatin methacrylamide/TiO 2 films was in the range of 471-758 %, which was enough to prevent wound beds from exudates accumulation. And in vitro degradation test in PBS showed that the three-dimensional structure of all samples basically remained unchanged although more than or nearly half the mass of specimens decreased after 4 weeks' degradation, and the pH levels of all sample solutions were maintained in an adequate range of 6.5-7.4 for cell and tissue growth during the whole process. The antibacterial activities of the films against E. coli and S. aureus were measured via a shake flask test and demonstrated good performance after the importation of TiO 2 nanoparticles. Cytotoxicity testing revealed that all films had no cytotoxicity and showed favorable adherence in the presence of L929 cells. The results suggest that hybrid hydrogel films hold potential for antibacterial wound dressing and tissue engineering scaffold applications.

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The chalcopyrite-type CuInSe 2 is a remarkable material for thin film solar cells owing to its electronic structure and optical response. Single-phase sphere-like CuInSe 2 nanocrystallite particles were prepared by a facile noninjection method with triethanolamine as the complexing agent and the solvent simultaneously. The period of the reaction was the key to form single-phase CuInSe 2 nanocrystals at 240 o C. TEM, XRD, XPS, EDX investigations were performed to characterize the morphology and the detailed structure of as-synthesized CuInSe 2 nanocrystals. All of the analysis results proved that the synthesized nanocrystals were pure phase and close to the stoichiometric ratio rather than a simple mixture. The band gap of the obtained CuInSe 2 nanocrystals was 1.03 ± 0.03 eV.