Molecular level evaluation on HEMA interaction with a collagen model

摘要

Objective. 2-Hydroxyethylmethacrylate (HEMA) diffuses in wet dentin and promotes adhesion during dentin priming and bonding. We have investigated the molecular level interaction between HEMA and a collagen model by using saturation transfer difference (STD) NMR. Methods. The binding of HEMA to collagen was preliminarily investigated by suspending demineralized human dentin powders in a 4mM HEMA solution for 1h and measuring the decrease in the HEMA concentration on a spectrophotometer. The molecular level interaction of HEMA with atelocollagen, which was used as a collagen model, was investigated by STD-NMR spectroscopy. Results. The HEMA concentration in the suspension did not change, indicating that HEMA did not bind to dentin collagen. This was confirmed by STD-NMR; when the atelocollagen resonance was saturated, no saturation was propagated to HEMA and no STD signals were detected. Significance. The HEMA protons were not near the atelocollagen surface, indicating HEMA did not interact with atelocollagen. The collagen fibrils may be surrounded by water molecules in dentin/bond interfaces, which prevent the direct HEMA binding interaction.