Analysis of hydroxyapatite surface coverage by amelogenin nanospheres following the Langmuir model for protein adsorption
Analysis of hydroxyapatite surface coverage by amelogenin nanospheres following the Langmuir model for protein adsorption
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DOI：
10.1007/s00223-002-1099-1
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发表时间：
2003-05-01
影响因子：
4.2
通讯作者：
Moradian-Oldak, J
中科院分区：
文献类型：
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作者：
Bouropoulos, N;Moradian-Oldak, J
釉原蛋白组装成纳米球被认为是釉质细胞外基质框架稳定性的关键因素，它为最初的釉质磷灰石晶体成核和生长提供了支架。评估吸附等温线是为了研究牙釉蛋白纳米球与溶液中羟基磷灰石晶体相互作用的性质，其中定义了它们的组装状态和粒径分布。我们报道了重组小鼠牙釉蛋白（rM179）在合成羟基磷灰石晶体上的吸附等温线可以使用 Langmuir 模型来描述，表明牙釉蛋白纳米球作为具有确定吸附位点的结合单元吸附在磷灰石晶体的表面上。吸附亲和力和最大吸附位点分别为19.7×10(5)L/mol和6.09×10(-7)mol/m(2),r(2)值为0.99。在吸附实验条件下了解了牙釉蛋白纳米球的组成和粒径分布，我们计算了纳米球的数量以及每个纳米球群体在最大吸附时所覆盖的晶体表面积。发现总最大结合覆盖了面积单位的 64%。这一观察结果支持了釉原蛋白与磷灰石表面的结合是选择性的并且仅发生在某些位点的推测。
The assembly of amelogenin protein into nanospheres is postulated to be a key factor in the stability of enamel extracellular matrix framework, which provides the scaffolding for the initial enamel apatite crystals to nucleate and grow. Adsorption isotherms ware evaluated in order to investigate the nature of interactions of amelogenin nanospheres with hydroxyapaite crystals in solution, where their assembly status and particle size distribution are defined. We report that the adsorption isotherm of a recombinant mouse amelogenin (rM179) on synthetic hydroxyapatite crystals can be described using a Langmuir model indicating that amelogenin nanospheres adsorb onto the surface of apatite crystals as binding units with defined adsorption sites. The adsorption affinity and the maximum adsorption sites were 19.7 x 10(5) L/mol and 6.09 x 10(-7) mol/m(2), respectively, with an r(2) value of 0.99. Knowing the composition and particle size distribution of amelogenin nanospheres under the condition of adsorption experiments, we have calculated the number of nanospheres and the crystal surface area covered by each population of nanospheres at their maximum adsorption. It was found that total maximum binding covers 64% of the area unit. This observation supports the speculation that amelogenin binding onto apatite surface is selective and occurs only at certain sites.