摘要
Mesoporous silica nanoparticles （MSN） were coated by pH-responsive polymer chitosan-poly （methacrylic acid） （CS-PMAA）. This nano drug delivery system showed good application prospects and the polymer-coated microspheres were promising site-specific anticancer drug delivery carriers in biomedical field. A continuous detection of pH-responsive drug delivery system in cells in situ, utilizing MSN/CS-PMAA composite microspheres, was pro- posed. Two kinds of different cell lines, tumor cell line （Hela） and normal somatic cells （293T）, were used to inves- tigate the behaviours of the drug loaded system in the cells. Conclusions could be drawn from the fluorescent im- ages obtained by confocal laser scanning microscopy （CLSM）, modified drug-loaded microspheres （MSN/CS-PMAA） were ingested into cells more easily, the uptake of DOX@FITC-MSN/CS-PMAA by HeLa/293T cells were performed at pH 7.4/pH 6.8, DOX was released during the ingestion process, fluorescence intensity de- creased with time because of efflux transport and photo-bleaching. Fluoresence detection by flow cytometry was performed as comparison. The continuous fluorescent observation in situ could be widely used in the pH-responsive releasing process of drug delivery system in the cells.
Mesoporous silica nanoparticles （MSN） were coated by pH-responsive polymer chitosan-poly （methacrylic acid） （CS-PMAA）. This nano drug delivery system showed good application prospects and the polymer-coated microspheres were promising site-specific anticancer drug delivery carriers in biomedical field. A continuous detection of pH-responsive drug delivery system in cells in situ, utilizing MSN/CS-PMAA composite microspheres, was pro- posed. Two kinds of different cell lines, tumor cell line （Hela） and normal somatic cells （293T）, were used to inves- tigate the behaviours of the drug loaded system in the cells. Conclusions could be drawn from the fluorescent im- ages obtained by confocal laser scanning microscopy （CLSM）, modified drug-loaded microspheres （MSN/CS-PMAA） were ingested into cells more easily, the uptake of DOX@FITC-MSN/CS-PMAA by HeLa/293T cells were performed at pH 7.4/pH 6.8, DOX was released during the ingestion process, fluorescence intensity de- creased with time because of efflux transport and photo-bleaching. Fluoresence detection by flow cytometry was performed as comparison. The continuous fluorescent observation in situ could be widely used in the pH-responsive releasing process of drug delivery system in the cells.
基金
the National Natural Science Foundation of China，the Shanghai Committee of Science and Technology
