We prepared FA-targeted and 10-hydroxycamptothecin loaded chitosan nanoparticles (FA-HCPT-NPs) with a combination of emulsion-solvent evaporation and chemical crosslinking method. In vitro cytotoxicity test to the Human Cervix Carcinoma cells (HeLa) was evaluated by cell morphology and internalization observation. The specicity of the FA-HCPT-NPs targeting cancerous cells was demonstrated by comparative intracellular uptake of HCPT-NPs and commercial availible HCPT injection. Laser confocal scanning imaging proved that FA-HCPT-NPs could greatly enhance up-take by HeLa cells. The morphological changes of HeLa cells showed the FA-HCPT-NPs could inhibit HeLa cells more effectively than HCPT-NPs and HCPT. The results indicated that the novel FA-HCPT-NPs could be a potential drug delivery system for tumor cell-selective targeting therapy.

We report a new type of biochemical materialmultifunctional paclitaxel-loaded poly lactide-lecithin (PLA-lecithin) microbubbles which has been developed with a method of ultrasonic double emulsion solvent evaporation (UDES) combined with lyophilization. Bubbles were characterized to be hollow, well dispersed andwith size of 300nm~2um. Paclitaxel loading efficiency could reach up to 12%, and bubbles with different size and different lecithin content showed varied drug release characteristics but all displayed slow-release and ultrasound controlled properties, illustrating the ultrasound responsive drug release effect of the combination of microbubbles and ultrasound.

Drug loaded PLA (or PLGA) mirobubbles that combine properties of ultrasound imaging contrast agents and drug carriers suffer from low encapsulation efficiency and difficulty to destruction with diagnosis ultrasound. In this paper, a new type of multifunctional paclitaxel-loaded poly lactide-lecithin (PLA-lecithin) microbubbles has been developed with a method of ultrasonic double emulsion solvent evaporation (UDES) combined with lyophilization, and single-factor of ultrasonic time was studied to influence bubble size and drug loading efficiency. Bubbles were characterized to be well dispersed, with size of 300nm~2um, and showed increased ultrasound imaging on rabbit liver and heart after intravenous injection.