Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, O-okayama 2-12-1, Tokyo 152-8550, Japan.
Langmuir. 2011 Jun 21;27(12):7645-53. doi: 10.1021/la200621p. Epub 2011 May 26.
A quartz crystal microbalance with dissipation (QCM-D) technique was employed to detecting the protein adsorption and subsequent osteoblast-like cell adhesion to hydroxyapatite (HAp) nanocrystals. The interfacial phenomena with the preadsorption of three proteins (albumin (BSA), fibronectin (Fn), and collagen (Col)), the subsequent adsorption of fetal bovine serum (FBS), and the adhesion of the cells were investigated. The QCM-D measured the frequency shift (Δf) and dissipation energy shift (ΔD), and the viscoelastic properties of the adlayers were evaluated using ΔD-Δf plot and Voigt-based viscoelastic model. The Col adsorption significantly showed higher Δf, ΔD, elasticity, and viscosity values as compared to the BSA and Fn adsorption, and the subsequent FBS adsorption depended on the preadsorbed proteins. The ΔD-Δf plot of the cell adhesion also showed a different behavior depending on the surfaces, and the Fn- and Col-modified surfaces showed the rapid mass and ΔD changes by forming the viscous interfacial layers with cell adhesion, indicating that the processes were affected by the cellular reaction through the extracellular matrix (ECM) proteins. The confocal laser scanning microscope images of adherent cells showed a different morphology and pseudopod on the surfaces. The cells adhered to the surfaces modified with the Fn and Col had significantly uniaxially expanded shapes and fibrous pseudopods, and those modified with the BSA had a round shape. Therefore, the different cell-protein interactions would cause the arrangement of the ECM and the cytoskeleton changes at the interfaces, and these phenomena were successfully detected by the QCM-D and Voigt-based model.
采用石英晶体微天平耗散（QCM-D）技术检测了纳米羟基磷灰石（HAp）晶体上蛋白质的吸附以及随后成骨样细胞的黏附。研究了三种蛋白质（白蛋白（BSA）、纤维连接蛋白（Fn）和胶原蛋白（Col））的预吸附、随后的胎牛血清（FBS）吸附以及细胞黏附的界面现象。QCM-D 测量了频率变化（Δf）和耗散能量变化（ΔD），并通过 ΔD-Δf 图和基于 Voigt 的粘弹性模型评估了吸附层的粘弹性。与 BSA 和 Fn 吸附相比，Col 吸附表现出更高的Δf、ΔD、弹性和粘性值，随后的 FBS 吸附取决于预吸附的蛋白质。细胞黏附的 ΔD-Δf 图也表现出不同的行为，取决于表面，并且 Fn 和 Col 修饰的表面通过与细胞黏附形成粘性界面层而迅速发生质量和 ΔD 变化，表明这些过程受到细胞反应的影响通过细胞外基质（ECM）蛋白。黏附细胞的共焦激光扫描显微镜图像显示了表面上不同的形态和伪足。黏附在 Fn 和 Col 修饰表面上的细胞具有明显的单轴扩展形状和纤维状伪足，而黏附在 BSA 修饰表面上的细胞具有圆形形状。因此，不同的细胞-蛋白质相互作用会导致 ECM 和细胞骨架在界面处的排列发生变化，这些现象可以通过 QCM-D 和基于 Voigt 的模型成功检测到。
