Honokiol-camptothecin loaded graphene oxide nanoparticle towards combinatorial anti-cancer drug delivery.

Honokiol (HK) is a natural product isolated from the bark, cones, seeds and leaves of plants belonging to the genus Magnolia. It possesses anti-cancer activity which can efficiently impede the growth and bring about apoptosis of a diversity of cancer cells. The major concerns of using HK are its poor solubility and lack of targeted drug delivery. In this study, a combinatorial drug is prepared by combining HK and camptothecin (CPT). Both CPT and HK belong to the Magnolian genus and induce apoptosis by cell cycle arrest at the S-phase and G1 phase, respectively. The combinatorial drug thus synthesised was loaded onto a chitosan functionalised graphene oxide nanoparticles, predecorated with folic acid for site-specific drug delivery. The CPT drug-loaded nanocarrier was characterised by X-ray diffractometer, scanning electron microscope, transmission electron microscope, UV-vis spectroscopy and fluorescence spectroscopy, atomic force microscopy. The antioxidant properties, haemolytic activity and anti-inflammatory activities were analysed. The cellular toxicity was analysed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT assay) and Sulforhodamine B (SRB) assay against breast cancer (MCF-7) cell lines.