Preparation Of Size-controllable Drug Loaded Nano-particles Based On Flash Nano-precipitation Method

Flash nano-precipitaion(FNP)is a new and simple method to prepare polymeric nanoparticles(NPs)contained organic active substance in very short time.Compared with traditional dialysis method,its superiority lies in the short preparation time,the whole process would be finished in few seconds.So,it has gained wide attention for its advantages in prepare dug-loaded NPs in recent years.This paper aimed at conducting further studies on the preparation of NPs by FNP technology.Methoxy poly(ethylene glycol)-b-polycaprolactone(mPEG-b-PCL)was selected as the polymer to encapsulate drug(?-carotene),both of mPEG and CL have good biocompatibility,CL also has good biodegradability.In this paper,various amphiphilic block copolymers with different molecular weights and molecular structure were synthesized and characterized by 1H NMR,GPC and fluorescence spectrophotometer.Then,based on the synthesized block copolymers and(3-carotene,a series of drug-loaded NPs were prepared by FNP.The effects of solvent ratio,polymer concentration,molecular hydrophilic/hydrophobic proportions and molecular weight on the final prepared di?block polymeric NPs were investigated.Experimental results showed that the size of di-block polymeric NPs decreased by increasing the solvent ratio or hydrophilic proportion.Under the same proportion of the hydrophilic moieties,the size of NPs were decreased by increasing the molecular weight.The NPs were more stable and their size distribution became narrower upon increasing polymer concentrations.Moreover,this paper conducted a preliminary exploration on the preparation of tri-block polymeric NPs by FNP.However,it remained to be further studied because of its' bad stability.Finally,compared with traditional dialysis method,FNP has lots of advantages.The experimental results showed that,the NPs prepared by FNP method presented high drug loading ratio and narrow distribution.Through above research,the size-controllable drug-loaded NPs were successfully prepared by using FNP.This paper provided basis for further research and application of FNP.