Preparation of liposomes containing benzophenanthridine alkaloid sanguinarine and evaluation of its cytotoxic activity

Abstract

Sanguinarine is a plant alkaloid with relatively low toxicity and high antiangiogenic, antitumour and antiviral potential. In order to increase its bioavailability and effectiveness, sanguinarine liposomes were prepared by a reverse phase evaporation method and characterised. Dynamic light scattering showed mean liposome size of 65 ± 11 nm, zeta-potential equal to -54 ± 1.2 mV, and polydispersity index equal to 0.26. The encapsulation efficiency was 78.6 ± 5.1%. The study on experimental models showed a prolonged sanguinarine release from liposome preparations. Liposomal sanguinarine showed dose-dependent cytotoxic activity in vitro on B16 (murine melanoma) and HeLa (human cervical carcinoma) cell lines. The highest cytotoxicity was observed on B16 cell line (IC50 6.5 μM). HeLa cell line cytotoxicity was relatively lower, equal to 8.03 μМ. Compared with free sanguinarine, liposomal sanguinarine may have advantages for in vivo anticancer therapy, due to its lower toxicity and 'passive targeting' as a result of enhanced permeability of tumour vessels.