Study On The Preparation Of Anticancer Drug Incorporated Ploy(lactic-co-glycolic Acid) Microspheres

Cancer is one of the major diseases which pose a threat to human health in modern, changing the delivery is a developing trend in oncology research. Microsphere as a novel controlled release drug delivery system has become a hot research at home and abroad.In this paper, anticancer drugs docetaxel and 5-fluorouracil as model drug, PLGA as a carrier, microspheres were prepared by emulsification - solvent evaporation. Emulsion and solvent evaporation process are two important factors to determine the nature of the microspheres by emulsification - solvent evaporation. These two processes are affected by many parameters, such as the oil phase polymer concentration, emulsifying speed, ratio of ingredients, volume ratio of oil phase to water one in emulsion and the concentration of emulsifier,. This paper examines these technological factors on particle size and encapsulation efficiency of microspheres and other properties; the effect of nano-hydroxyapatite properties of microspheres; the mechanism of microsphere degradation and release; microspheres on the role of tumor suppressor. The results showed that: the higher the concentration of PLGA, the larger particle size microspheres, and the higher the encapsulation efficiency; the higher emulsifying speed, the smaller size of microspheres, and the lower encapsulation efficiency; the smaller volume ratio of oil phase to water one in emulsion, the smaller particle size of microspheres, and the lower encapsulation efficiency; the mass ratio of medicine and polymer, the higher encapsulation efficiency; the higher emulsifier concentration, the smaller particle size of microspheres, and the lower encapsulation efficiency. PLGA / nHA composite microspheres compared with pure PLGA microspheres, encapsulation efficiency was increased, and the surface of composite microspheres present slightly "rough" obvious holes. The results microsphere degradation and release show that: degradation time of PLGA was about 30 days, due to the role of nHA medium and PLGA/nHA composite microspheres degrads slower than pure PLGA microspheres.The release of microspheres can be divided into three stages: an initial burst release, followed by a lag period and a second accelerated release. Models were used to simulate the spread of drugs and the degradation process effection on drug release, and prejudged the impact of trend. in the initial release phase, drug release controlled by diffusion; drug release was controled by the diffusion and degradation in lag period; microspheres were degraded fullly and the drugs were all released in a second accelerated release. MTT results showed that: inhibitory effect on cancer cell growth of PLGA / nHA composite microspheres were better than PLGA microspheres and DTX.