Preparation And Properties Research Of Medical Chitosan Nanospheres

Chitosan molecular was one of bio-polymer nano-materials which could be biologicaldegraded in vitro and in vivo, with good biocompatibility and no cytotoxicity. Chitosannanospheres which were synthesized by chitosan molecular was one of biological genecarriers and have a good prospect in gene therapy and bone regeneration.Objectives: To prepare the bio-functionnal chitosan nanospheres and explore the factorsduring the preparation of the nanospheres， then characterize the nanospheres and study itspharmaceutical characteristics and biological properties.Methods: Chitosan nanospheres were prepared by inverse microemulsion method andwere characterized for their size、zeta potential and morphologies with Laser particle sizeanalyzer、 FESEM and TEM. The biological properties of chitosan nanospheres wereevaluated by Confocal Laser Scanning Biological microscope (CLSBM) study and MTTassay.Results: The concentration and pH of chitosan solution、volume ratio of water/oilphase、surfactant、acetone、Reaction temperature can impact the diameter of chitosannanospheres. The morphology of the chitosan nanospheres finally prepared was mostlyspherical and well distributed, with a diameter distribution of （179±12.85）nm and zetapotential of﹢（31.4±5.87）mV. The morphology of the FITC labeled chitosan nanospheresfinally prepared was mostly spherical and well distributed with a diameter distribution of（363.2±94）nm and zeta potential of－（24.2±6.8）mV. The morphology of the chitosannanospheres loading pEGFP was mostly spherical and well distributed, with a diameterdistribution of （227.9±83.1） nm and zeta potential of＋（11.4±6.16） mV. Goodbiocompatibility and low cytotoxicity of the chitosan nanospheres prepared was confirmedby MTT assay. Uptake of the FITC labeled chitosan nanospheres by MC3T3cells wasquantified by Confocal Laser scanning Biological microscope.Conclusions: The chitosan nanospheres、the FITC labeled chitosan nanospheres andthe chitosan nanospheres loading pEGFP could be prepared by inverse microemulsionmethod.The chitosan nanospheres finally prepared had good biocompatibility. The FITClabeled chitosan nanospheres finally prepared could be uptaken by MC3T3-E1cells. Thechitosan nanospheres finally prepared is a new nano gene vector which can load pEGFP and the loading efficiency is28.8%.