Thermoresponsive PEG-Based Polymer Layers: Surface Characterization with AFM Force Measurements
Thermoresponsive PEG-Based Polymer Layers: Surface Characterization with AFM Force Measurements
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DOI：
10.1021/la903007v
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发表时间：
2010-03-02
期刊：
影响因子：
3.9
通讯作者：
Fery, Andreas
中科院分区：
文献类型：
--
作者：
Kessel, Stefanie;Schmidt, Stephan;Fery, Andreas
基于聚（2-（2-甲氧基乙氧基）乙基甲基丙烯酸酯-共-寡聚（乙二醇）甲基丙烯酸酯）[P（MEO（2）MA-co-OEGMA）]的温度响应性聚合物涂覆的表面允许在细胞附着和脱离之间切换。在这里，我们调查的温度依赖性的聚合物涂层和胶体探针之间的表面相互作用，在水介质中通过原子力显微镜（AFM）的力距离测量。从AFM的回缩曲线的粘附力的分析确定了两种制度的共聚物在温度低于和高于下临界溶解温度（LCST）。而在25摄氏度的表面与聚合物在溶胀状态的相互作用是由排斥力为主，在37摄氏度的表面相互作用切换到吸引力和更强的粘附力被检测到的AFM。重复运行几个愈合/冷却循环表明，切换表面特性提供了可再现的粘附力值。时间依赖性的测量给洞察的开关动力学，表明细胞响应耦合到聚合物动力学，但可能受到细胞重排。
Thermoresponsive polymer-coated surfaces based on poly(2-(2-methoxyethoxy)ethyl methacrylate-co-oliog(ethylene glycol) methacrylate) [P(MEO(2)MA-co-OEGMA)] allow switching between cell attachment and detachment. Here, we investigate the temperature-dependent surface interactions between the polymer coating and a colloidal probe in an aqueous medium by means of atomic force microscopy (AFM) force-distance measurements. The analysis of the adhesion forces from AFM retraction curves indentifies two kinds of regimes for the copolymer at temperatures below and above the lower critical solution temperature (LCST). Whereas at 25 degrees C the surface interactions with the polymer in the swollen state are dominated by repulsive forces, at 37 degrees C the surface interactions switch to attractive forces and a stronger adhesion is detected by AFM. Running several healing/cooling cycles repeatedly shows that switching the surface properties provides reproducible adhesion force values. Time-dependent measurements give insight into the switching kinetics, demonstrating that the cell response is coupled to the polymer kinetics but probably limited by the cellular rearrangements.