Facile preparation of water-soluble multiwalled carbon nanotubes bearing phosphorylcholine groups for heat generation under near-infrared irradiation

In the present study, water-soluble molecular complexes between carboxylic acid-functionalized multiwalled carbon nanotubes (MWCNTs) and biocompatible poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) were prepared by hand grinding. MWCNTs could be solubilized in phosphate-buffered saline using this simple method. The suspended concentration of MWCNTs was found to increase with increasing polymer concentration and pH of the solution. Heat generation from the complexes was studied upon irradiation with near-infrared (NIR) radiation at a wavelength of 808 nm. The results demonstrated that MWCNTs absorbed light and generated heat when the molecular complex was irradiated by NIR. The solution temperature increased with increasing MWCNT concentration and irradiation time.