Docetaxel （DTX） was incorporated into albumin nanoparticles to form the docetaxel loaded nanoparticles （DTX-NPs） with a high-pressure homogenization method. The purpose of this procedure was to improve the solubility, stability and biocompatibility of DTX. In our study, particle size, zeta potential, size distribution, and encapsulation efficiency were investigated. The crystalloid state of DTX in nanoparticles was further determined by the X-ray diffraction technique. The hemolysis rate, pharmacokinetics and pharmacodynamics of the DTX-NPs were analyzed and compared with the injectable docetaxel solution （DTX-Sol）, which was fabricated according to the formulation of the commercial Taxotere. It demonstrated that the DTX-NPs were prepared successfully with these properties, including the （193±4） nm size, （-30±1） mV zeta potential and 69%±2% encapsulation efficiency. Higher stability was achieved in the lyophilized nanoparticles compared to that in the nanoparticle suspension. Furthermore, less hemolysis effect was observed in the DTX-NPs than that in the DTX-Sol. The pharmacokinetic and pharmacodynamic behaviors of the DTX-NPs were similar as that of DTX-Sol based on the in vivo experiments. In conclusion, albumin nanoparticles may act as a useful and safe carder for DTX.
Aim To prepare a self-emulsifying microemulsion of 9-nitrocamptothecin （9-NC ME） for intravenous injection and investi- gation of its pharmacokinetic profiles in normal SD rats. Methods 9-NC ME was optimized in terms of droplet size and lack of drug precipitation following aqueous dilution using a pseudo-ternary phase diagram. Physicochemical properties of 9-NC ME were evaluated. 9-NC ME was intravenously administered via tail vein in healthy rats. Results A stable microemulsion was formulated consisted of soybean oil as oil phase, EPC/Tween-80 as emulsifier, and anhydrous ethanol as co-emulsifier. The droplets of the microemulsion were spherical shape with mean diameter of 38.3 ± 4.0 nm after 1：20 dilution with 5% glucose injection. The pharmacokinetic parameters of 9-NC ME after intravenous administration in rats were t1/2 of 0.97 ± 0.14 h, A UC0-8 of 372.77 ±49.62 ng·h·mL^-1 and MRT of 1.40 ± 0.21 h which were 1.4-fold, 1.65-fold, and 1.4-fold more than those of 9-NC solution （P〈0.01）. Conclusion The results suggested that 9-NC ME was a promising drug delivery system and it was expected to provide a novel 9-NC injection for cancer patients.
