Research On The Preparation And Release Performance Of PCL Matrix Drug Delivery System

The traditional treatment of diseases such as oral administration and injection generally requires periodic administration of drugs,which has low drug utilization and large side effects.At the same time,due to the continuous absorption and excretion of drugs by the human body,the compliance of patients with chronic diseases who need long-term administration is poor,thus affecting the control of the disease.Therefore,the controlled release drug delivery system with targeting,drug release stability and low side effects has become the focus of research.In this paper,a matrix drug delivery system was prepared with polycaprolactone as drug loading matrix and 5-fluorouracil as release drug.The preparation process,mechanical properties and drug release performance of the drug delivery system were studied.The main research contents are as follows:Firstly,based on the analysis of the preparation methods of common drug delivery system and the factors affecting the molding quality of drug delivery systems,polycaprolactone drug delivery systems were prepared by solvent evaporation by injection molding.The effects of parameters such as molecular weight of polycaprolactone,injection pressure and drug-polymer ratio on the preparation quality of drug delivery system were studied experimentally.Secondly,the tensile and compression properties of polycaprolactone with different molecular weight and drug content were tested.The parameters such as elastic modulus,yield strength and tensile strength of the drug delivery system were tested experimentally.By comparing with the strength parameters of polycaprolactone artificial bone,it was proved that the prepared drug delivery system met the expected requirements in mechanical properties and met the standard of human implantation.Thirdly,the simulation model of drug delivery system is established and the drug release performance is studied.The material compatibility,crystallinity and drug dissolution characteristics of the drug delivery system were studied by scanning electron microscope(SEM)and differential scanning calorimeter(DSC).The drug release mechanism of the drug delivery system was clarified,and the best ratio of polycaprolactone to drug was obtained.Based on Fick's diffusion law,the drug release model of drug delivery system under the action of diffusion mechanism is derived.The effects of drug delivery system radius and drug content on drug release were studied by using MATLAB program to simulate the drug release process.Finally,taking the zero-order drug release as the goal,the differential evolution method was used to optimize the radius and drug content of the drug delivery system.According to the optimized parameters,the drug delivery system was prepared,and the phosphate buffer solution was used to simulate body fluid.The in vitro drug release experiments of the drug delivery system were carried out to verify the correctness of the drug release model and optimization results.