Enhanced Antitumor Efficacy Of Doxorubicin Encapsulatedwithin Halloysite Nanotubes

Objectives: Investigate the antitumor efficacy of doxorubicin encapsulated Halloysite Nanotubes, to provide new strategy for the clinical treatment of gastric cancer.Methods: In this study, HNTs/LIP/DOX composites were obtained by successively encapsulating HNTs with LIP,and stirring the formed HNTs/LIP with DOX solution. FESEM, XRD, TGA, TEM UV-Vis ATR-FTIR and ATR-FTIR were used to characterize the samples. The loaded efficiency of DOX、stability and in vitro drug release were also studied. The in vitro anticancer activity of the HNTs/LIP/DOX was tested by MTT. Establish ectopic implantation cancer model in back of nude mouse. The antitumor efficacy and biocompatibility were monitored by measuring the tumor volume and testing the blood routine, serum biochemistry at different time points.Results: We show that an exceptionally high loading efficiency of 22.01 ± 0.43 % can be obtained when the concentration of HNTs and DOX is 3 mg/mL and 1 mg/mL, respectively. TEM,FESEM and thermogravimetric analysis confirmed the feasibility of Lip modification of HNTs. XRD results show that DOX can be absorbed on the surface and cavum of HNTs in the manner of physical adsorption. In vitro drug release study demonstrates that much more DOX can be released under acidic pH condition(pH = 5.4) than that of physiological pH condition. Cell viability assay and in vivo experimental results reveal that HNTs/DOX display a significantly higher therapeutic efficacy in inhibiting the growth of the MFC mice gastric cancer cells than free DOX at the same DOX concentrations. In addition, the lifespan of tumor bearing mice in HNTs/DOX treated group were prolong obviously. Finally, the HNTs/DOX possess an excellent hemocompatibility..Conclutions: The hemo-/cytocompatiable HNTs/DOX possess higher therapeutic efficacy in inhibiting the growth of the MFC mice gastric cancer cells than free DOX drug at the same DOX concentrations.