Effect of HEMA adsorption on the stability of native and denatured type I tendon collagen.

ABSTRACT

Adsorption behavior and stabilization/destabilization effects of 2-hydroxyethyl methacrylate (HEMA) on a bovine tendon collagen (BTC) (type I), either native (N) or thermally denatured (D), were studied by IR spectroscopy and differential scanning calorimetry (DSC). The amount of HEMA adsorbed was larger on BTC(D) than on BTC(N), because BTC(D) had a larger specific surface area (SSA) as revealed from SSA measurement. Denaturation temperature (Td) of BTC(N), measured by DSC in aqueous HEMA solution, decreased from 63 degrees C to 40 degrees C with increasing HEMA concentration (CHEMA) up to 20 wt%. This destabilization might be caused by the loss of hydrophobic stabilization of the helix structure as CHEMA was increased. At CHEMA > 20 wt%, the structure of collagen was restabilized presumably due to the dehydration effect conferred by HEMA at higher concentration. BTC(D) with little helix content, however, showed only a weak endothermic peak in the DSC measurement and the Td at 40 degrees C was independent of CHEMA.