BRIGE: Hindered-Diffusion Grayscale Surface Functionalization

这一扩大参与的工程研究启动补助金(Brige)为开发一种新的纳米级表面制造和图案化技术提供了资金。该方法利用化学物质通过三维聚合物网格的受阻扩散来创建伪灰度功能化表面图案；三维聚合物衬底用作掩膜来控制分子从液体储存库到目标图案化表面的扩散路径长度。以这种方式，可以控制表面功能化化学品的放置和这些化学品的局部密度。将进行实验以表征网目密度和通过聚合物的溶质运移速率，这些信息将被用来推导受阻扩散速率与聚合物和溶质基本性质之间的关联预测关系。这些关系将被用来生成所描述的图案化机制的数值计算机模型，并且结果将被实验验证。最后，组合的数值和实验结果将被用于创建确定性算法，用于为任何所需的化学/图案组合选择优化的聚合物几何形状和网目密度。选择性化学沉积可用于改变许多表面属性，包括结合亲和力、可制造性、疏水性和免疫反应。目前最先进的表面图案化只使用户能够制作微尺度的二元图案，其中的区域要么完全没有化学修饰，要么包含单一均匀的化学密度。如果成功，这项研究将提供一种廉价的方法，以高精度的方式产生表面图案，并达到目前方法无法达到的几何复杂性水平。对低成本、可广泛获得的材料的关注将使这一过程立即为大量制造商和研究人员所用。灰度表面图案化的应用多种多样，包括用于药物开发的高通量结合研究，用于医学测试的便携式生物传感器，用于微流体和自组装的流体运动控制，以及细胞行为的定量研究。此外，在这项研究中开发的受阻扩散研究和分析模型将在组织工程、靶向药物输送和医疗诊断等由这种传输机制管理的大量领域提供宝贵的工具。

This Broadening Participation Research Initiation Grant in Engineering (BRIGE) provides funding for the development of a novel nanoscale surface fabrication and patterning technique. This method utilizes the hindered diffusion of chemicals through a three-dimensional polymer mesh to create pseudo-grayscale functionalized surface patterns; the three-dimensional polymer substrate serves as a mask to control the diffusion path length of molecules from a liquid reservoir to the target patterning surface. In this manner, both the placement of surface-functionalized chemicals and the local density of these chemicals can be controlled. Experiments will be conducted in order to characterize mesh density and solute transport rates through polymers and this information will be used to derive predictive relationships correlating hindered diffusion rate to basic polymer and solute properties. These relationships will be used to generate numerical computer models of the described patterning mechanism, and the results will be validated experimentally. Finally, the combined numerical and experimental results will be used to create deterministic algorithms for selecting optimized polymer geometry and mesh density for any desired chemical/pattern combination.Selective deposition of chemicals can be used to modify a number of surface properties, including binding affinity, manufacturability, hydrophobicity, and immune response. The current state-of-the-art in surface patterning only enables the user to make microscale binary patterns, where regions are either completely absent of chemical modification or contain a single uniform chemical density. If successful, this research will represent an inexpensive method for producing surface patterns in a highly accurate manner with a level of geometric complexity that is unattainable with current methods. The focus on low-cost, widely-available materials would make this process immediately accessible to a large number of manufacturers and researchers. Applications for grayscale surface patterning are numerous and varied, including high-throughput binding studies for pharmaceutical development, portable biosensors for medical testing, control of fluid movement for microfluidics and self assembly, and quantitative studies of cell behavior. In addition, the hindered-diffusion studies and analytical models developed in this research will provide invaluable tools in the large number of fields governed by this transport mechanism, including tissue engineering, targeted drug delivery, and medical diagnostics.