Preparation of co-loading photosensitizer/UCNPs/dihydroartemisinin liposomes and evaluation of its in vitro antitumor activity / 中草药

ABSTRACT

Objective: To develop the photosensitizer rose-bengal (RB)/upconverting nanoparticles (UCNPs)/dihydroartemisinin (DHA) co-encapsulated liposomes (LIP-RUD) and preliminarily study the in vitro inhibition effects on human colon cancer. Methods: The hydrophilic UCNPs were synthesized by solvothermal and ligand conversion and RB/UCNPs/DHA were encapsulated by thin-film dispersion method to obtain LIP-RUD. HPLC was performed to determine the loading ratio (LR) of RB and DHA. Zetasizer was used to evaluate the physiochemical properties of liposomes. The production of ROS was investigated by SOSG probe. In vitro cellular uptake of LIP-RUD was observed by confocal laser scanning microscopy (CLSM) and the cytotoxicity on HCT-116 cells was estimated by MTT assay. Results: LIP-RUD showed an average particle diameter of 150 nm with zeta potential of -12 mV. The LR of RB and DHA were 54.5% and 86.5%, respectively. The energy conversion efficiency of UCNPs and RB reached 49.8%. After irradiation, the singlet oxygen (1O2) was generated and 74.9% of encapsulated DHA was released from LIP-RUD at 12 h, which showed an improvement of up to 25.6% compared to the absence of laser irradiation group. In cellular experiments, LIP-RUD exerted improved cytotoxicity on HCT-116 cells. IC50 was 15.33 μmol/L under laser irradiation. Conclusion: LIP-RUD provides a new thought in the treatment of human colon cancer by the combination of photodynamic therapy (PDT) and chemotherapy, which is expected to enhance the penetration depth of PDT and the therapeutic effect of combination therapy.