Type I Collagen Adsorption Behavior on the Control and Modified Surface of Polylactide Coating

Abstract

Knowledge of the bio-macromolecules adsorption on polylactide (PLA) was essential to the application of PLA-based biomedical materials. This study presented the adsorption behavior of type I collagen on control (CH3-enriched) and modified (introduced COOH– and CONH2– respectively) PLA surfaces by quartz crystal microbalance with energy dissipation measurements (QCM-D) and atomic force microscopy (AFM). The results showed that the Langmuir adsorption isotherms were obtained, indicating a monomolecular layer adsorption of collagen on PLA coatings. Adsorption of collagen could reach equilibrium more quickly on the modified surfaces than on the control. Large amounts of collagen (1522.2 ng·cm−2) was assembled tightly on the COOH-enriched surface of PLA, owing to the electrostatic attracting. However it was inhibited on the CONH2-enriched surface because of its increasing hydrophilicity. A netlike structure was formed on the control and COOH-enriched surfaces, while only a few of braching fibril was found on the CONH2-enriched surface. The behaviour of protein adsorption on the surfaces with different groups might effect the next stage of cell adhesion on scaffold.