Non-covalently Functionalized Carbon Nanotube by Hyaluronic Acid Based Azo Polymer for Photothermal Elimination of Tumor Cells

Photothermal therapy has been renowned for its non-invasive and highly precise approach in cancer treatment. Therefore, the synthesis of suitable photothermal agent has attracted wide attention. In this study, a non-covalent method for modifying carbon nanotube by hyaluronic acid based azo polymer was proposed. Hyaluronic acid based azo polymer was attached to the surface of carbon nanotube via the π-π interaction and hydrophobic interaction between azo moiety and the wall of carbon nanotube. After the self-assembly process, the modification was demonstrated with transmission electron microscopy, infrared spectra and thermal gravimetric analysis. The modified carbon nanotube (HA-MWCNT) was endowed with both the tumor cell targeting property of hyaluronic acid and the excellent photothermal effect of carbon nanotube, enabling it to serve as photothermal agent for eliminating tumor cells. Upon co-culture with HeLa cells, HA-MWCNT was proved to exhibit low cytotoxicity without irradiation. After being irradiated with infrared laser light, the HeLa cells cultured with HA-MWCNT perished due to the heat generated by the endocytosed HA-MWCNT, which attested to the potential of HA-MWCNT as a photothermal agent for cancer treatment.