Carmofur-Loaded Pluronic P123 Polymeric Micelles: Preparation and Characterization

The purpose of the present study was to investigate the preparation and characterization of a polymeric micellar formulation of Carmofur (HCFU) with Pluronic P123. The polymeric micelles of HCFU with Pluronic P123 were prepared by thin-film hydration method. The characteristics of micelles were studied, including morphology, particle size distribution, entrapment efficiency, and drug loading; stability studies, DSC analysis, and in vitro release of HCFU from micelles were carried out. The results showed that the HCFU-loaded micelles had a mean size of approximately 30 nm with narrow size distribution and a spherical shape. The encapsulation efficiency, drug loading, and the drug concentration of the optimized nanoparticles were 65.76 +/- 1.47%, 1.48 +/- 0.08%, and 227.785 mu g.mL(-1) respectively. The stability test indicated that the leakage rate of HCFU from micelles reached 26.64% at ambient temperature after 6 months. To improve the stability of micelles, lyophilized HCFU-loaded micelles were prepared by adding sufficient quantum of trehalose into the homogeneous micelles suspension, and the obtained lyophilized micelles showed good redispersibility as well as homogeneity. The mean diameters of lyophilized micelles were 31.1 nm. The formation of HCFU-loaded micelles was validated by DSC, which indicated that HCFU was successfully encapsuled into micelles. HCFU was continuously released from Pluronic P123 micelles in release medium containing 0.05% Tween 80 and 0.1 mol.L-1 HCL solution for 48 hours at 37 degrees C. These results indicated that Pluronic P123 micelles could improve the solubility of poorly soluble lipophilic drugs.