Chondrocyte behaviors on poly- -lactic acid (PLLA) membranes containing hydroxyl, amide or carboxyl groups

Hydrophilic groups, i.e. hydroxyl (–OH), carboxyl (–COOH) or amide (–CONH2) were introduced onto the poly- -lactic acid (PLLA) membrane surfaces via the photo-induced grafting copolymerization of the corresponding monomers, i.e. hydroxyethyl methacrylate, methacrylic acid or acrylamide, respectively. Chondrocyte culture was used to study the correlation between the cell behaviors and the hydrophilic functional groups. The results showed that the cytocompatibility of the PLLA membranes with hydroxyl or amide groups on the surface was greatly improved compared to that of the original PLLA membrane. However, the PLLA membrane with carboxyl groups on the surface had even worse cytocompatibility though possessed a similar hydrophilicity.