Tretinnikov O N, Kato K, Ikada Y
Research Center for Biomedical Engineering, Kyoto University, Japan.
J Biomed Mater Res. 1994 Nov;28(11):1365-73. doi: 10.1002/jbm.820281115.
To produce a bone-bonding polymer surface that is capable of inducing deposition of a hydroxyapatite (HA) layer in the body fluid, an organophosphate polymer was covalently immobilized onto a high-density polyethylene film by surface graft polymerization of a phosphate-containing monomer. The grafted film was immersed in simulated physiologic solution (SPS). The chemical composition and structure of the formed apatite layer as well as its bonding strength to the polymer surface were investigated. To distinguish the effect of phosphate groups on the deposition of apatite layer from the simple calcium absorption by the anion, a comparative study was done using a polyethylene film with surface immobilized carboxylic groups. Calcium phosphate deposition was observed on all the materials investigated, but the kinetics, composition, deposit amount, and bonding strength of the new phase were found to be significantly different among the modified materials, depending on the density and chemical nature of the surface immobilized ionic groups. It was found that the polymeric materials modified by surface graft polymerization of a phosphate-containing monomer produce a carbonated HA layer firmly bonded with the material upon immersion in SPS. Carboxyl groups in the grafted layer was not enough to activate bonding with the HA layer.
为了制备一种能够在体液中诱导羟基磷灰石（HA）层沉积的骨结合聚合物表面，通过含磷单体的表面接枝聚合将有机磷酸酯聚合物共价固定在高密度聚乙烯薄膜上。将接枝薄膜浸入模拟生理溶液（SPS）中。研究了形成的磷灰石层的化学成分、结构及其与聚合物表面的结合强度。为了区分磷酸基团对磷灰石层沉积的影响与阴离子对钙的简单吸收作用，使用表面固定有羧基的聚乙烯薄膜进行了对比研究。在所研究的所有材料上均观察到磷酸钙沉积，但发现新相的动力学、组成、沉积量和结合强度在改性材料之间存在显著差异，这取决于表面固定离子基团的密度和化学性质。结果发现，通过含磷单体的表面接枝聚合改性的聚合物材料在浸入SPS后会产生与材料牢固结合的碳酸化HA层。接枝层中的羧基不足以激活与HA层的结合。
