Preparation And In Vitro Anti-tumor Activity Of Liposomes Encapsulating Hydroxycamptothecin-cyclodextrin Inclusion Complexes

Objective:To optimize the preparation technology to manufacture hydroxycamptothecin inclusion liposomes, and do preliminary evaluation of their quality and in vitro anti-tumor activity.Methods:(1) The neutralization agitation method was used to prepare hydroxycamptothecin inclusion and film evaporation method was utilized to manufacture hydroxycamptothecin inclusion complex liposomes. The two preparation methods were optimized by single factor and orthogonal test to get the best preparation process and verified.(2)The phase solubility method, differential scanning calorimetry and infrared spectroscopy were used to identify the prepared inclusion complex.(3) The particle morphology, size, in vitro release and stability were regarded as quality evaluation of the hydroxycamptothecin inclusion liposomes.(4) The hepatoma cells (HepG-2), lung cancer cells (A549), gastric cancer cells (SGC-7901) were used as model cell lines for preliminary evaluation of anti-cancer effect of hydroxycamptothecin inclusion liposomes by MTT colorimetry, flow experiments, apoptosis staining compared with available commercially hydroxycamptothecin. Results:(1)The best process manufacturing hydroxycamptothecin inclusion by neutralization agitation method was follows:the ratio of guest and host materials was1:1, the concentration of2-hydroxypropyl-beta-cyclodextrin was10%, the inclusion temperature was50℃, stirring speed was400rpm, the resulting inclusion was of average inclusion rate of66.69%,14.67%of drug loading; relative solubility method, differential scanning calorimetry and infrared spectroscopy proved the formation of hydroxycamptothecin inclusion.(2) The best process manufacturing hydroxycamptothecin inclusion liposomes was follows:20mg/mL of soybean lecithin concentration, the ratio of soybean lecithin and cholesterol ratio was5:1(g/g), the ratio of drug and lipid was1:10(g/g),100r/min rotary evaporation was film-forming, hydrated2h, ultrasonicated for10min at30%of the power probe; the prepared inclusion liposomes had average inclusion rate of70.55%, drug-loading was3.90%, the average particle size of119.7nm, the zeta potential of-45.6mV, having a sustained release effect, the hydroxycamptothecin inclusion liposomes had better stability at4℃.(3) The hydroxycamptothecin inclusion liposomes exhibited better inhibition of three kinds of cancer cells above, and their anti-cancer effect was at dose-dependent manner; The inhibition of cancer cells was stronger than48h after the cancer cells were stronger than commercially available hydroxycamptothecin. Conclusion:Neutralization agitation method and thin film evaporation method are used to manufacture hydroxycamptothecin inclusion liposomes with better encapsulation efficiency, drug-loading content, stability, sustained-release effect and stronger anti-cancer activity.