Monodisperse thermoresponsive microgels with tunable volume-phase transition kinetics
Monodisperse thermoresponsive microgels with tunable volume-phase transition kinetics
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DOI：
10.1002/adfm.200700379
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发表时间：
2007-11-23
影响因子：
19
通讯作者：
Weitz, David A.
中科院分区：
文献类型：
--
作者：
Chu, Liang-Yin;Kim, Jin-Woong;Weitz, David A.
提出了一种控制温敏性聚N-异丙基丙烯酰胺（PNIPAM）微凝胶体积相变动力学的简便方法。利用微流控装置制备了具有球形空隙的单分散PNIPAM微凝胶。这些微凝胶的膨胀和收缩反应与球形空隙的温度变化进行比较与那些无空隙的微凝胶的相同大小和化学组成的使用相同的微流控装置制备。结果表明，PNIPAM微凝胶与空隙响应更快的温度变化相比，其无空隙的同行。此外，诱导的空隙结构不会对微凝胶的平衡体积变化产生不利影响。因此，微凝胶的体积相变动力学可以通过控制空隙的数量和尺寸来微调。这种方法所提供的制造灵活性，控制性和简单性使这些微凝胶吸引了从药物输送系统和化学分离到化学/生物传感和致动器的应用。
A facile method to control the volume-phase transition kinetics of thermo-sensitive poly(N-isopropylacrylamide) (PNIPAM) microgels is presented. Monodisperse PNIPAM microgels with spherical voids are prepared using a microfluidic device. The swelling and shrinking responses of these microgels with spherical voids to changes in temperature are compared with those of voidless microgels of the same size and chemical composition prepared using the same microfluidic device. It is shown that the PNIPAM microgels with voids respond faster to changes in temperature as compared with their voidless counterparts. Also, the induced void structure does not have a detrimental effect on the equilibrium volume change of the microgels. Thus, the volume phase transition kinetics of the microgels can be finely tuned by controlling the number and size of the voids. The flexibility, control, and simplicity in fabrication rendered by this approach make these microgels appealing for applications that range from drug delivery systems and chemical separations to chemical/biosensing and actuators.