Amino Activation On Silica Surface And Study On Preparation And Properties Of Antibacterial Nanocomposite Materials

Glass slides have a wide range of applications in life scientific research. However,because of the glass slides without surface activation, whose silicon-oxygen bond isstable and lack of sufficient chemical activity, it could not fully meet our needs.Therefore, in recent years, glass slide surface modification research is graduallyarousing researcher interest. Surface modification with small molecules alone or incombination with short crosslinkers is the main approach in a heterogeneousimmunoassay.Currently, with the development of biotechnology and materials science,amino-modified glass slides in immune bio-detection, polymer-coated materials andso on show great potential applications.Core/shell structure of nanoscale composites show the different character andfunction due to their different chemical composition, which greatly extend itsapplication prospect in various fields.Guanidinium antibacterial materials haverecently attracted considerable scientific attention due to their unique advantages suchas high antibacterial activity, high stability, easy for storage, reproducibility,non-corrosive, non-toxic and low cost. They have been widely utilized in variousfields, e.g., medical devices, hospitals, water purification systems, food packaging,food preservation and sanitation.In this paper, poly（glycidyl methacrylate）（PGMA）was chosen as the cladding object due to its high reactivity caused by superficialepoxy groups and good resistance to acid, heat, weather and solvent.Silica has good chemical stability, high specific surface area, the surface rich inhydroxyl groups with organisms having the good compatibility characteristics, It hasbecome an excellent carrier material used widely in catalytic, adsorption andseparation, biological and other fields. Nano-silver is a broad spectrum, and not easyto produce drug-resistant material, its antibacterial activity after mercury only, thussilver antimicrobial material is the most common inorganic antimicrobial agent. Thesilver ions are easy to aggregate in medium, Now, the silver-based fungicides areusually supported as a carrier such as zeolite, phosphate, clay, wherein the effect of silica as the carrier of the silver-based antimicrobial agent is most ideal.In this thesis, the presence of PAM on glass slide is firmly demonstrated by thepresence of polar chlorine Cl （2p） peaks and the change in the intensity of elementalN （1s） peaks in the high resolution XPS spectra. AFM and SEM provide detailedimages of the surface morphology of the PAM layer. A major factor determiningnodule density and surface morphology is the solvent of the reaction. PAM grown onglass slide under anhydrous condition resulted in the formation of continuousmonolayer. The grown nodules can provide a continuous undulating sheet across glassslide. However, PAM grown on glass slide surface under aqueous conditionpolymerized to a two-tier structure. Different applications of PAM layer have differentrequirements, according to its modification methods and reaction conditions toprepare for PAM layers with specific thickness, condensation d egree and amino groupdensity. The application of PAM modified glass slide will be greatly promoted invarious fields, especially in biology and nanoscale material applications.Novel magnetic-antimicrobial-fluorescent multifunctional hybrid microsphereswith well-defined nanostructure were synthesized by the aid of poly（glycidylmethacrylate）（PGMA） template. The hybrid microspheres were fully characterizedby scanning electron microscopy （SEM）, transmission electron microscopy （TEM）,fourier transform infrared （FTIR）, X-ray diffraction （XRD）, and digital fluorescencemicroscope. The as-synthesized microspheres PGMA, amino-modified PGMA（NH2-PGMA） and magnetic PGMA （M-PGMA） have spherical shape with smoothsurface and fine monodispersity. M-PGMA microspheres are super-paramagnetic andtheir saturated magnetic field are4.608emu·g-1, which made M-PGMA could beefficiently separated from aqueous solution by an external magnetic field. Afterpoly（haxemethylenguanidine hydrochloride）（PHGH） functionalization, the resultantmicrospheres exhibit excellent antibacterial performance against both Gram-positiveand Gram-negative bacteria. The fluorescence feature originated from the quantumdots CdTe endowed the hybrid microspheres with biological functions such astargeted localization and biological monitoring functions. Combination of magnetism,antibiosis and fluorescence into one single hybrid microsphere opens up thepossibility of extensive study of multifunctional materials and widens the potentialapplications.By introducing the assembly technology of metal ions and the nano technology， silver loaded active Si02nano, whose antibacterial property being evaluated with themethod of antibacterial circle have been prepared by impregnation method，and theantibacterial mechanisms and the relative characteristics have been studied. ActiveSiO₂and its nano-composition have been characterized. The influences of preparationfactors of silver-loaded active Si02nano compositions on the silver contents and theantibacterial properties and the relation between the silver contents and theantibacterial properties have been studied. The quantitative relationship modelsbetween the silver contents and the size of antibacterial circle and between thepreparation factors and the silver contents have been established．And the optimizedpreparation factors and the optimum silver content have been obtained．Not only havenew nano—compositions with antibacterial property been developed and thetheoretical foundation for the antibacterial agents to be further studied and widelyused been laid， but also have the science basis for utilization of mineral resourcesbeen provided and a new application field been found out.To sum up, this thesis design the preparation of polyacrylamide on glass slidesurface, study on preparation and properties of the ibacterial polymer nanocompositematerial and a kind of inorganic antibacterial nanomaterial, respectively.