Silicon Nanoparticles As Gene Transfection Vectors

Efficient DNA transfection is critical for gene tranfer and gene therapy research ,it is make great progress that highly efficient and safety gene carrier ,but the mechanisms responsible for DNA uptake are unknown, current nonviral transfection methods are enable to enhancement by a variety of chemical, these chemicals include particulates, lipids, and polymer complexes that optimize DNA complexation or condensation, membrane fusine , endosomal release , or nuclear targeting , which are the presumes barriers to gene delivery 0 Most chemical enhancements produce a moderate increase in gene delivery and a limited increase in gene expression, as a result , the efficiency of transfection and level of gene expression after nonviral DNA delivery remain low. Although the traditional method for gene transfer is low DNA concentration at the cell surface, or more concentration DNA come into the cell but DNA segment was breakout, the gene express is low too.We synthesized silica nanoparticles (SP) with covalently linked sodium surface modifications and demonstrated their ability to electrostatically bind and protect plasmid DNA. After these nanoparticles are modified by different concentration sodium iodine or sodium chloride , complex with green flourescence protein (EGFP-N1) plasmid DNA, the potential of absorbing and protecting DNA detected by agrose gel electrophoresis. we found that these nanoparticles have the potential to adsorb DNA and are resistant to serum digestion at acid pH, nanoparticle -DNA (EGFP-N1) complexes could transfer into HT1080 cell, even more efficient than the cationic lipids examined in this study in vitro. These nanoparticle might be utilised as DNA carriers for gene delivery in vitro.In order to test in vivo toxicity of silica nanoparticles, intravenous and/or intra-abdominal the silica nanoparticles to mice(lOO) at different concentration, there were no significant toxicity; transmission electromicroscope was done and revealed the accumulation of SNAP in the cells of brain, liver, spleen, lung, kidney, intestine, prostate and thetestis without any pathological cell changes or mortality that they passedthrough the blood-brain, blood-prostate and blood-testis barriers. Thesefindings indicate that the silica nanopaticals we generated has goodbiological characteristics as a potential promising vector for gene transfer,gene therapy and drug delivery.