| Summary: | 碩士 === 大同大學 === 化學工程學系(所) === 93 === A series of composite hydrogels containing silver nanoparticle used for bioadhesive were prepared from acrylic acid (AA), poly (ethylene glycol) methyl ether acrylate (PEGMEA) and silver nanoparticles through the ex-situ polymerization. The silver nanoparticles with narrow size distribution were prepared by reducing silver nitrate solution with ascorbic acid. The influence of the content of silver nanoparticles into bioadhesive hydrogel on the equilibrium swelling ratio, mechanical property, electrical conductivity and inactivation of Escherichia coli (E. coli) was investigated in this study. Results showed that the swelling ratios of the composite gels were decreased by silver nanoparticles into the gels, but not decreased with an increase of the content of silver nanoparticles. In addition, the crosslinking density and shear modulus of these hydrogels do not increase with an increase of the content of silver nanoparticles. The adhesive force of the present (APECAg series) hydrogels was not obviously changed. Finally, the initial rate of E. coli inactivation for APECAg series hydrogels showed excellent antibacterial properties.
A series of nanocomposite hydrogels used for bioadhesive were prepared from acrylic acid (AA), poly (ethylene glycol) methyl ether acrylate (PEGMEA) and silver nanoparticles through UV irradiation in-situ polymerization. The factors that affect the silver nanoparticles size include reaction temperature, stirring rate, the concentration of precursor solution and the concentration ratio of the chelating agent and the precursor solution (AgNO3(aq)). The most important factor is the concentration ratio of the chelating agent and the precursor solution. Results showed that the silver nanoparticles dispersed onto hydrogel surface and the mean silver particle size is 72.4 nm. The electrical conductivities of the nanocomposite hydrogels increase with increasing the silver nanoparticle content. The crosslinking density and shear modulus have no alteration with increasing the silver nanoparticle content. The adhesive force gradually decreases with increasing the silver nanoparticle content. And, the initial rate of E. coli inactivation also increases with the silver nanoparticle content. This is because silver nanoparticles were successfully reduced on the hydrogel surface.
Two series of different charge nanocomposite hydrogels were prepared from N-isopropylacrylamide (NIPAAm), intercalated mica (IM) and N, N'-methylene-bis-acrylamide (NMBA) (NIM-series); NIPAAm, IM, trimethyl (acrylamido propyl) ammonium iodide (TMAAI) (NTIM-series), respectively, in this study. The mica was intercalated with different contents of intercalant, trimethylammonium chloride (TMAACl), based on the anion exchange capacity (AEC) of mica. The swelling behaviors, mechanical properties and drug-release behaviors were compared from these two series gels. Their microstructures and morphologies were also examined by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). Results showed that zeta potentials for the NIM series gels increase with increase in intercalation content of mica, (from –11 mV to –6 mV), but the zeta potentials for NTIM series gels decrease with increase in intercalation content of mica, (from +36 mV to +28 mV). The swelling ratios for the NIM gels are lower than those for NTIM series gels. The gel strengths and crosslinking densities for NIM series gels are higher than corresponding NTIM series gels. But the diffusion coefficient and penetration velocity for NIM series gels are lower than corresponding NTIM series gels. The drug-release behaviors for these two series gels are also investigated in this study.
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