Chemically modified multiwalled carbon nanotubes improve the cytocompatibility

Multiwalled carbon nanotubes (MWCNTs) have been widely used in materials science. This study was designed to evaluate the dispersions and cytocompatibilities of chemically modified MWCNTs, carboxyl MWCNTs (MWCNTs-COOH) were separately reacted with ethylenediamine (EDA) and polyethyleneimine (PEI) via thionyl chloride, as well as polyamideamine (PAMAM) via EDC-NHS click chemistry. Chemically modified MWCNTs were successfully obtained and characterized by TEM, FTIR, and TGA. The dispersities of MWCNTs were measured as: MWCNTs-COOH < MWCNTs-PAMAM < MWCNTs-EDA < MWCNTs-PEI. MTT assay demonstrated chemically modified MWCNTs improved the cytocompatibilities compared to the unmodified MWCNTs, and the cytotoxicity of MWCNTs-PEI was least (P < 0.05). Therefore, chemically modified MWCNTs can increase the dispersion of MWCNTs and improve their cytocompatibilities.