Preparation Of PLGA Nanoparticles And Its Application As Drug Delivery Vector For Cancer

Gensenoside Rg3(Gs-Rg3), extracted from the Panax ginseng, has multiple Parnacological activities, including anti-fatigue, anti-tumor, Platelet aggregation inhibition, enhancing immunity, memory improvement and so on. However, the absorption and metabolism of oral ginsenoside Rg3is too fast to maintain a sufficient concentration in plasma.Biocompatible and biodegradable PLGA (poly (lactic-co-glycolic acid) has shown significant potentialin drug delivery. With its gradual degradation in vivo, PLGA nanocapsules can release loading drugs little by little, which have shown excellent therapeutic effect.In the first part of this paper, PLGA/Rg3nanoparticles were prepared by In-situ S/O/W method. We examined the factors that may affect the properties of the nanocapsules, which includes the ultrasonic time, power and Rg3concentration in W/O emulsion. The scanning electronic microscopy image showed that all the nanoparticles prepared are sphere, with smooth surface.Rg3loading efficiency can reach68%. The releasing profiles of the PLGA/Rg3nanoparticles in PBS were measured. It can release it’s containing Rg3gradually, and70%of the total amount of Rg3was releasesd in40days. The cell cytotoxicity of the PLGA/Rg3nanoparticles in HepG2cells were studied by MTT method.The results showed that PLGA/Rg3nanoparticles can inhibit the prolification of HepG2cells in vitro, and the inhibition is time and dosage dependent.Chitosan (CS) is a kind of alkaline polysaccharide with good biological adsorption. It can interact with the negatively charged mucosa. PLGA nanoparticles can be modified with CS, and thus to improve its drug delivery efficiency.Diphtheria toxins (DT) and its mutants (DT389) can kill multiple tumor cells, which can be used in the treatment of cancer.In the second part of this paper PLGA/DT389-CS nanoparticles by W/O/W double emulsion-solvent evaporation method. PLGA/DT389nanoparticles modified with different amounts of CS were prepared. The MTT results showed that PLGA/DT389-CS nanoparticles can inhibit the prolification of HepG2cells more efficiently than PLGA/DT389nanoparticles.In conclusion, PLGA/Rg3nanoparticles were prepared with In-situ S/O/W method as well as PLGA/DT389-CS nanoparticles with W/O/W method. All the nanoparticles preparedwere studied by SEM. The loading efficiency and releasing profile were measured. MTT results showed that PLGA/Rg3and PLGA/DT389-CS nanoparticles can inhibit the prolification of HepG2cells in vitro. The application of these nanoparticles in cancer treatment will be studied further in the future.