Liposomes Encapsulating 10-Hydroxycamptothecin-Cyclodextrin Complexes and Their In Vitro Anti-Tumor Activities.

Manufacturing and characterizing hydroxycamptothecin inclusion liposomes, establishing their quality standard and testing their in vitro anti-tumor activity is of significance for potential application. The neutralization agitation method was used to prepare hydroxycamptothecin inclusion and film evaporation method was utilized to manufacture hydroxycamptothecin inclusion liposomes. The phase solubility method, differential scanning calorimetry and infrared spectroscopy were used to identify the prepared inclusion complex. The hydroxycamptothecin inclusion liposomes were characterized for particle morphology, size, in vitro release and stability. The hepatoma (HepG-2), lung cancer (A549), and gastric cancer (SGC-7901) cell lines were used as models for preliminary evaluation of anti-cancer effect from the hydroxycamptothecin inclusion liposomes, done by MTT colorimetry, cytometer experiments, and apoptosis staining. The anti-cancer evaluation was compared with commercially available hydroxycamptothecin. The results showed the hydroxycamptothecin inclusion was successfully prepared by neutralization agitation method. Phase solubility method, differential scanning calorimetry and infrared spectroscopy proved the formation of the hydroxycamptothecin inclusion. The hydroxycamptothecin inclusion liposomes were successfully prepared by film evaporation method. (2) The inclusions were found to be spherical, with average particle size of 119.7 nm, zeta potential of - 45.6 mV, average inclusion rate of 70.55%, and drug-loading was 14.60%. The inclusions were also found to have a sustained release effect, when compared to the commercially available hydroxyccamptothecine. The hydroxyccamptothecine inclusion liposomes had better stability at 4 degrees. (3) The hydroxycamptothecin inclusion liposomes also exhibited better inhibition effect for the three kinds of cancer cell lines above, when compared to the commercially available hydroxycamptothecin the anti-cancer effect being at a dose-dependent manner. Neutralization agitation and thin film evaporation methods can be used to manufacture hydroxycamptothecin inclusion liposomes with better encapsulation efficiency, drug-loading content, stability, sustained-release effect and stronger anti-cancer activity.