Interactions between cells and polymers are mediated by proteins, which are either secreted by cells and immobilized on the biomaterial surface, or absorbed from the medium. Poly (lactic acid) (PLA) is widely used in tissue engineering as a scaffold material, however anchorage-dependent cells such as osteoblasts do not attach, grow, and differentiate well on a hydrophobic surface. In this study, a hydrophilic polymer-poly (ethylene glycol) (PEG) was used to develop diblock polymers, Methoxy-terminated poly (ethylene glycol)-Poly (lactic acid) (MPEG-PLA) to investigate cell-biomaterial interactions. Osteoblasts were cultured on different composition of PEG-PLA films in serum free or serum condition. Lactate dehydrogense (LDH) assay was used to assess the cytotoxicity of the copolymers and cell attachment and proliferation on the polymer surfaces; furthermore cell morphology was visualized by Crystal Violet stain.

The results showed that MPEG-PLA films induced early osteoblast attachment in serum free condition and the higher content of PEG in the MPEG-PLA films the more cell attachment was noticed. No significant difference of cell attachment was observed on MPEG-PLA films between serum free and 10% serum culture condition. Crystal Violet stain demonstrated the same trend in the cell-spreading characteristics on the polymer surface.

In conclusion MPEG-PLA copolymer can enhance osteoblast attachment under serum-free condition, which implies a potential application in cell delivery therapy due to the restriction in animal products for human therapeutically goods.