NER: Controlling Transport of Nanosized Objects by Substrate-Grafted Polymeric Engines

这项工作的研究目标是开发制备多功能表面接枝聚合物组件的方法，这些组件可以作为引擎来操作，能够指导纳米物体的运动。该方法是：1)产生物理化学性质(接枝密度、相对分子质量)逐渐变化的表面接枝大分子组件和随着温度变化经历急剧和可逆转变的表面接枝的“智能”聚合物；2)开发表征工具来监测梯度上的传输；以及3)利用表面系留的梯度组件和热响应聚合物来演示纳米粒子的运动。理解“智能”聚合物表面如何直接传输纳米级物体有望对基础科学、技术和生命科学产生深远的影响。例如，揭示这种“智能”聚合物表面充当分子引擎的条件，能够控制纳米粒子的运动，可以用来设计新的材料组装方法，或者提供对表面功能吸附物质分配的洞察。此外，纳米粒子运动的基本原理可以用来理解蛋白质在人造表面上的吸附和从多组分蛋白质混合物中分离蛋白质。这项工作产生的社会效益包括(但不限于)更好的医疗药物设计或检测生物战剂的能力。

The research objective of this work is to develop methods of preparing multifunctional surface-grafted polymer assemblies that can operate as engines capable of directing motion of nanosized objects. The approach is to: 1) generate surface-grafted macromolecular assemblies with gradual variation of physico-chemical properties (grafting density, molecular weight) and surface-grafted "smart" polymers that undergo sharp and reversible transitions in response to temperature changes; 2) develop characterization tools for monitoring the transport on gradients; and 3) demonstrate motion of nanoparticles using the surface-tethered gradient assemblies and thermoresponsive polymers.Understanding how "smart" polymer surfaces direct transportation of nanosized objects is expected to have a profound impact on basic science, technology, and life sciences. For example, uncovering the conditions under which such "smart" polymer surfaces act as molecular engines capable of controlling the motion of nanoparticles can be utilized in designing novel methods of material assembly or providing insight into partitioning of functional adsorbates on surfaces. In addition, the basic principles of nanoparticle motion can be used to understand protein adsorption and protein separation from multicomponent protein mixtures on artificial surfaces. The societal benefits resulting from this work include (but are not limited to) better design of medical drugs or capability of detecting bio-warfare agents.