Conformational modifications of serum albumins adsorbed on different kinds of biomimetic hydroxyapatite nanocrystals
Conformational modifications of serum albumins adsorbed on different kinds of biomimetic hydroxyapatite nanocrystals
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DOI：
10.1016/j.colsurfb.2010.07.022
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发表时间：
2010-11-01
影响因子：
5.8
通讯作者：
Roveri, Norberto
中科院分区：
文献类型：
--
作者：
Iafisco, Michele;Sabatino, Piera;Roveri, Norberto
纳米级碳酸盐-羟基磷灰石代表了用于骨替代和生物分子递送的合适材料。其与血清蛋白的相互作用在器械植入过程中起着核心作用。本文研究了人血清白蛋白（HSA）和牛血清白蛋白（BSA）与两种尺寸、比表面积、结晶度和表面性质不同的仿生碳酸羟基磷灰石（CHA）的表面相互作用。BSA达到不同的最大覆盖率，随着CHA纳米晶的比表面积越大，尺寸越小，结晶度越低，呈片状形貌，BSA的最大覆盖率越高。相反，HSA在两种基质上的最大覆盖率没有显着差异。吸附等温线已被拟合的Langmuir和Freundlich模型，表明仿生羟基磷灰石基质的行为作为一个混合物的能量均匀和异质网站，由于其表面的障碍。通过傅里叶变换红外光谱（FT-IR）和圆二色性（CD），已经发现，环己二胺影响吸附的蛋白质的构象。FT-IR光谱表明，CHA表面上的蛋白质粘附导致两种蛋白质在两种基材上的螺旋度显著降低，作为涂覆程度以及β-结构中的修饰的函数。从基质解吸后在溶液中释放的HSA和BSA的CD光谱显示，虽然这两种蛋白质部分恢复其螺旋结构，但它们在其三级结构中显示出不同的行为。(C)2010 Elsevier B. V.保留所有权利。
Nanosized carbonate-hydroxyapatite represents a suitable material for bone substitution and delivery of biomolecules. Its interaction with serum proteins plays a central role in the process of implantation of a device. Herein, surface interactions of human (HSA) and bovine (BSA) serum albumin with two biomimetic carbonate-hydroxyapatites (CHA) differing for size, surface area, crystallinity degree and surface properties have been investigated. BSA reached a different maximum coverage, being higher with the CHA nanocrystals with the higher surface area, the smaller size, the lower crystallinity degree and the plate shape morphology. On the contrary, HSA did not show significant differences of maximum coverage on the two substrates. The adsorption isotherms have been fitted by the Langmuir and Freundlich models, showing that the biomimetic hydroxyapatite matrix behaves as a mixture of energetically homogeneous and heterogeneous sites due to its surface disorder. By using Fourier Transform Infrared Spectroscopy (FT-IR) and Circular Dichroism (CD) it has been found that CHAs affect the conformation of the adsorbed proteins. FT-IR spectroscopy shows that protein adhesion on CHA surface results in a significant reduction in helicity for both proteins on both substrates, as function of the coating extent as well as modification in the beta-structures. CD spectroscopy of the HSA and BSA released in solution after desorption from the matrices shows that, while both proteins partially regain their helical structure, they show a distinct behaviour in their tertiary structure. (C) 2010 Elsevier B.V. All rights reserved.