Preparation of a paclitaxel-loaded cationic nanoemulsome and its biodistribution via direct intratumoral injection.

In this study, a nano-preparation based on nanoemulsome (NES) modified with cetyltrimethylammonium bromide (CTAB) loading paclitaxel (PTX) was designed, and its biodistribution were explored after intratumoral (i.t.) administration on Heps tumor-bearing mice. The PTX-loaded nanoemulsome (PTX-NES) was prepared by using a solvent evaporation method and CTAB, chosen as a cationic material, was absorbed onto the surface of the NES via electrostatic interaction to yield paclitaxel-loaded cationic nanoemulsome (PTX-CTAB-NES). The MTT results exhibited that PTX-CTAB-NES (IC50: 0.50±0.035μg/mL in MCF-7 cells and 0.13±0.048μg/mL in SMMC-7721 cells) had the strongest cytotoxicity compared to Taxol (IC50: 0.88±0.054μg/mL in MCF-7 and 0.15±0.011μg/mL in SMMC-7721) and PTX-NES (IC50: 1.93±0.062μg/mL in MCF-7 and 0.32±0.027μg/mL in SMMC-7721). Body distribution of PTX revealed that the percent of PTX retained in the tumor after i.t. administration of PTX-CTAB-NES (approximately 92.99% at 0.167h and 15.35% at 48h) was higher when compared to that after i.t. injection of Taxol (approximately 58.94% at 0.167h and 0.83% at 48h) or PTX-NES (approximately 83.63% at 0.167h and 6.52% at 48h). Moreover, less PTX accumulated in liver, spleen, kidney, lung and heart after i.t. administration of PTX-CTAB-NES when compared with that after i.v. administration of PTX-CTAB-NES. In conclusion, PTX-CTAB-NES was a prospective in-situ delivery system for the therapy of tumor.