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 (MS_PCL) 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 MS_PCL increased, the hydrophilicity of the ACS-g-PCL copolymers decreased. Eventually, ACS-g-PCL microspheres with a diameter of 100-200 μm were fabricated by an emulsion evaporation method. Among them, the ACS-g-PCL copolymer with an MS_PCL 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 MS_PCL 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. [ABSTRACT FROM AUTHOR]