Thermo-Electro-Mechanics at Individual Particles in Complex Colloidal Systems
Thermo-Electro-Mechanics at Individual Particles in Complex Colloidal Systems
复制标题
DOI：
10.1021/acs.jpcc.9b06425
复制
发表时间：
2019-09-05
影响因子：
3.7
通讯作者：
Zheng, Yuebing
中科院分区：
文献类型：
--
作者：
Kollipara, Pavana Siddhartha;Lin, Linhan;Zheng, Yuebing
在恒定温度梯度下，盐离子在水溶液中的索雷特系数不同，可以产生热电场。尽管它们与细胞生物学和粒子操纵高度相关，但在涉及微米/纳米粒子、盐离子和分子的复杂胶体系统中理解和控制TE场仍然具有挑战性。在这种胶体系统中，挑战来自于与带电微米/纳米颗粒的热相互作用，其使颗粒周围的TE场失真。在这里，我们提供了一个框架TE场在胶体悬浮液中的各种离子和表面活性剂在单纳米粒子的水平。特别地，我们揭示了在温度梯度下，电介质颗粒周围的TE场的空间变化，以确定颗粒上的热电捕获力。从TE力分布预测的捕获刚度的理论结果匹配以及与实验的光热电捕获刚度的颗粒的解决方案中的温度梯度是很好地控制由激光束。通过深入了解TE场和复杂系统中的力，我们的框架和方法可以扩展到工程TE场，用于对具有不均匀表面形态的任意形状颗粒进行多功能光热电操作，并推进细胞生物学的科学研究。
It has been well established that thermoelectric (TE) field can arise from different Soret coefficients of salt ions in aqueous solution under constant temperature gradient. Despite their high relevance to cellular biology and particle manipulations, understanding and controlling of TE field in complex colloidal systems that involve micro/nanoparticles, salt ions, and molecules have remained challenging. In such colloidal systems, challenge arises from the thermal interactions with charged micro/nanoparticles that distort the TE field around the particles. Herein, we provide a framework for TE field in colloidal suspensions with various ions and surfactants at the single-nanoparticle level. In particular, we reveal the spatial variation of TE field around a dielectric particle under temperature gradient to determine the thermoelectric trapping force on the particle. Our theoretical results on the trapping stiffness predicted from the TE force profile match well with the experimental optothermoelectric trapping stiffness of particles in the solutions where the temperature gradient was well controlled by a laser beam. With insights into the TE field and force in complex systems, our framework and methodology can be extended to engineer the TE field for versatile optothermoelectric manipulations of arbitrarily shaped particles with nonuniform surface morphology and to advance the scientific research in cellular biology.