Evaluation of Anticancer Activity of Organo-Montmorillonites and their Plumbagin-Nanohybrids

Plumbagin is a naphthoquinone derivative obtained from medicinal plant and displayed cytotoxic activity against several cancer cells. To increase the cytotoxicity of plumbagin on cancer cell lines, it was adsorbed by organo-montmorillonites, used as an adsorbent and prepared by the ion-exchange reaction between three quaternary ammonium surfactants and sodium ion in montmorillonite. Three plumbagin-nanohybrids were successfully synthesized by adsorption of plumbagin in the interlayer space of the organo-montmorillonites and accessed antiproliferation effect on three cancer cells including human colon cancer, human cervical cancer and human breast cancer cell lines and a non-cancer cell line. The organoclays and plumbagin-nanohybrids were characterized by X-ray diffraction, IR and CHN analysis. The combination index (CI) value was used to determine the degree of organo-montmorillonites and plumbagin interaction, indicating a synergistic cytotoxicity between plumbagin and all three organo-montmorillonites on MCF-7 cell proliferation, while they showed additive effect on Vero cell.