Study On Preparation Of Drug-loaded Fibrous Membrane And Drug Release By Electrospinning

Tumors are one of the important factors that endanger human health today.Traditional systemic drug treatment can cause great harm to the human body.Therefore,it is necessary to develop local drug delivery systems with small side effects for the treatment of tumors.Electrospinning technology has been widely used in biomedical engineering since its emergence.The electrospun nanofibers with reasonable structure and characteristics are proved to be promising drug carriers due to the advantages of high load capacity,high encapsulation effect and easy operation.Till now,many substances,from antibiotics to proteins,DNA,RNA,living cells and various growth factors,had been loaded into the electrospun fibers.In this thesis,the lipid-soluble drug paclitaxel(PTX)and water-soluble drug(DOX)were encapsulated into the nanofibers separately by blending electrospinning and coaxial electrospinning to achieve a sustained release.The main research results are as follows:Firstly,PTX-loaded lignin nanoparticles(PLNPs)with good morphology were successfully prepared by solvent exchange method,and the average particle size was about72 nm.The in vitro cell culture experiment showed that the drug-free nanoparticles(LNPs)had good biocompatibility,and the survival rate of cervical cancer cells(He La)was higher than 80%.While,PLNPs significantly reduced the cell viability of He La cells.With the increase of the loaded drug concentration,the cell survival rates were decreased.Then the blending electrospinning technology was used to encapsulate the PTX-loaded lignin nanoparticles into PVA-PVP nanofibers.The drug-loaded nanofiber scaffolds(PVAPVP/PLNPs)with special stucture had good thermal stability,mechanical properties and hydrophilicity.Compared with the drug-loaded nanoparticles,PVA-PVP/PLNPs nanofibers have a longer drug release period.On the seventh day,the survival rate of He La cells on the PVA-PVP/2%PLNPs nanofiber scaffold was only 21%.The water-soluble drug DOX was encapsulated in the nanofibers by coaxial electrospinning technology.DOX was distributed inside the water-soluble polymer PVA,and an outer layer prepared with a mixture of PCL and gelatin was also formed to control the drug release.The special core-shell structure showed good sustained-release properties of drugs.There is no burst release of drugs and DOX can be released for more than 5 days with a cumulative release rate of about 83%.Cell culture experiments showed that it can effectively inhibit the growth of He La cells,and at the seventh day,the survival rate on fibrous scaffolds with high drug loading was less than 20%.In conclusion,the PVA-PVP/PLNPs and PCL-GEL/PVA-DOX nanofiber membranes prepared by electrospinning had good biocompatibility.And they can inhibit the growth of cancer cells effectively,and have good application potential in tumor treatment.