Preparation and entrapment efficiency determination of solid lipid nanoparticles loaded levodopa

OBJECTIVE Levodopa solid lipid nano-particles(LDP-SLN)was prepared,and an efficient method for determination of entrapment efficiency(EE%)was established.METHODS LDP-SLN was prepared through the micro-emulsion technology prepared by drawing ternary phase diagram,The morphology was examined by transmission electron microscope,the particle size was determined by laser granularity equipment,and the entrapment efficiency(EE%)was determined with the Sephadex gel chromatogram.The mean particle size,drug entrapment efficiency(EE%)and long-term physical stability of the SLN were investigated.RESULTS The loaded SLN dispersion was a stable milk-like suspension,and was uniform spheres under the electron microscope,the mean particle size was 108 nm,multi-factor spread was 1.153.There were no obvious changes of the particle size and entrapment efficiency at 4 ℃within two month.The method for determination of entrapment efficiency showed a good linearity range from 2 to100 mg· L-1(r=0.999 9),the precision met the requirements,SLN on drug-eluting after the separation and recovery met the requirements.CONCLUSION The LDP-SLN prepared by micro-emulsion technology has good stability,the method for determination of entrapment efficiency established is applicable to the system entrapment efficiency of SLN.The physical stability was relative stable.