Modification of carboxylated multiwall nanotubes with benzotriazole derivatives and study of their anticancer activities

In vitro and in vivo results indicate that functionalized carbon nanotubes are promising for the development of unique anticancer drugs. Since therapeutic and pharmacologic agents could functionalize the structure of carbon nanotubes, we report for the first time three-component condensation reactions consisting of multiwalled carbon nanotube-COCl (MWNTCOCl), diazonium sulfonated salt and phenol derivatives to produce novel anticancer agents. The functionalized carboxylated multiwall nanotubes were then characterized by FT-IR, Raman, SEM, TEM, and solubility test. The functionalized MWNTs exhibited good aqueous solubility. Furthermore, the cytotoxic activity of the MWNT-COOH (A) as well as its functionalized carboxylated multiwall nanotubes (MWNT-CO-2-(1-hydroxynaphthalen-2-yl)-2H-benzo[d][1,2,3]triazole-5-sulfonic acid (B), MWNT-CO-2-(2-hydroxy-1-nitrosonaphthalen-3-yl)-2H-benzo[d][1,2,3]triazole-5-sulfonic acid (C) and MWNT-CO-2-(2-hydroxy-5-nitrophenyl)-2H-benzo[d][1,2,3]triazole-5-sulfonic acid (D)) was tested against human gastric cancer MKN45 and human Colon cancer SW742. In vitro cytotoxicity studies represented a significant enhancement in the cytotoxic capability of f-MWNTs, suggesting these drugs improve drug antitumor activity. Therefore, the highly versatile functionalized carboxylated multiwall nanotubes could potentially be considered as anticancer candidates.