Riddet Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand.
J Colloid Interface Sci. 2013 Mar 15;394:458-66. doi: 10.1016/j.jcis.2012.11.058. Epub 2012 Dec 5.
The adsorption of caseins from sodium caseinate (SC) and whey proteins from whey protein isolate (WPI) on to particles of hydroxyapatite (HA) was studied. Confocal microscopy and zeta-potential measurements showed that both caseins and whey proteins bound to HA, resulting in an increase in the absolute value of the zeta-potential of the particles. This adsorption improved the suspension stability of the HA particles in water. For both protein sources, there was a preference in the protein adsorption: in the order β-casein > α(s)-casein > κ-casein for sodium-caseinate-coated particles; in the order β-lactoglobulin > α-lactalbumin for WPI-coated particles. The adsorption of caseins and whey proteins on to HA could be fitted using a simple Langmuir model, suggesting a single layer adsorption of caseins and whey proteins on to the HA surface. Possible mechanisms involved in the interaction between milk proteins and HA are discussed, in relation to the structure and the surface properties of both milk proteins and HA particles.
研究了来自酸钠盐（SC）的酪蛋白和来自乳清蛋白分离物（WPI）的乳清蛋白在羟磷灰石（HA）颗粒上的吸附情况。共焦显微镜和动电势测量表明，酪蛋白和乳清蛋白都与 HA 结合，导致颗粒的动电势绝对值增加。这种吸附提高了 HA 颗粒在水中的悬浮稳定性。对于这两种蛋白质来源，蛋白质的吸附存在偏好性：在钠酪蛋白包覆的颗粒中，β-酪蛋白＞α(s)-酪蛋白＞κ-酪蛋白；在 WPI 包覆的颗粒中，β-乳球蛋白＞α-乳白蛋白。酪蛋白和乳清蛋白在 HA 上的吸附可以用简单的 Langmuir 模型拟合，表明酪蛋白和乳清蛋白在 HA 表面的单层吸附。讨论了乳蛋白与 HA 之间相互作用涉及的可能机制，与乳蛋白和 HA 颗粒的结构和表面性质有关。
