Homogeneous synthesis of amino‐reserved chitosan‐graft‐polycaprolactone in an ionic liquid and the application in cell cultivation

The homogeneous preparation of amino-reserved chitosan-graft-polycaprolactone copolymer (ACS-g-PCL) was achieved in 1-butyl-3-methylimidazolium acetate via a protection - ring-opening graft polymerization - deprotection procedure. The molar substitution of PCL (MSPCL) in ACS-g-PCL copolymers was in the range 17.1 - 45.6 and could be well controlled by altering reaction conditions. The resultant ACS-g-PCL copolymers were soluble in some common organic solvents such as dimethylsulfoxide, ethanol and toluene. As the increment of MSPCL increased, the hydrophilicity of the ACS-g-PCL copolymers decreased. Eventually, ACS-g-PCL microspheres with a diameter of 100-200 mu m were fabricated by an emulsion evaporation method. Among them, the ACS-g-PCL copolymer with an MSPCL of 26.8 formed into porous microspheres. The fluorescence microscopy and cytotoxicity results suggested that all of the microspheres, especially the ACS-g-PCL microspheres with MSPCL of 17.1 and 26.8, showed high cell adhesion and cytocompatibility to the human osteosarcoma cell line (MG-63), indicating their great prospects in tissue engineering. (c) 2015 Society of Chemical Industry