Linear and Side-Functionalized Macromolecular Adsorbates for Enhanced Versatility in the Self-Assembly at Surfaces

项目编号：CBET: 0731168首席研究员：G. Kane jennings大学/机构：Vanderbilt大学标题：增强表面自组装多功能性的线性和侧功能化大分子吸附剂本项目将开发两类巯基端大分子吸附剂，用于在金属表面上自组装具有独特性能的分子厚膜。一类硫醇由具有不同末端的线性聚甲基组成，包括烷基、全氟烷基和端甲氧基低聚（乙二醇）基团。另一类是含有随机分布的功能侧链的聚亚甲基系链，包括羧酸、酯和非极性基团，以及烷基末端。这些新型的大分子吸附剂将通过多同源反应制备，这是一种高度控制的聚合反应，可以产生几乎单分散的长链醇，其长度和侧链组成可以控制，可以转化为硫醇，以便在不同的金属表面进行化学吸附。这些独特的吸附剂将被研究用于超快速和敏感的ph响应薄膜和3-D单层模板，用于图图化和关键整体膜蛋白的包裹和定向。知识价值。该项目将产生两种新的硫醇吸附剂，并将展示如何精确控制结构和组成的大分子可以与分子自组装相结合，以制备创新的新材料。线性类吸附剂有望产生最厚、最具保护性的单层膜，并将用于制备蚀刻、沉积、生物分子包裹和定向的模板。支链类吸附剂应该能够调整单层的结晶度，并为单层在反应膜领域开辟新的应用。对这些长链吸附物组装的研究将对分子膜形成过程中吸附物-吸附物相互作用（包括氢键和静电斥力）和溶剂-吸附物相互作用的作用产生根本性的见解。我们期望由这些吸附剂制备的薄膜能够定义稳定性、屏障性能和多功能性的新标准，同时呈现出技术上重要的表面，可以选择为低能量或生物惰性。更广泛的影响。所提出的薄膜可用于化学传感器的关键应用，防止腐蚀或蚀刻的保护屏障层，以及促进表面蛋白质取向的独特模板。当被固定化酶或其他受体结合时，对局部pH值有反应的膜可用于表明分析物化合物的存在。为了在传感方面具有商业意义，电影必须表现出巨大、快速和尖锐的反应。由于它们的疏水性，薄性和定制的组成，具有稀羧基侧基的薄膜应该是迄今为止制备的任何有机薄膜中对pH值反应最大，最快和最强烈的。这种高性能将为这些单层膜在化学传感器中的商业开发创造机会，其中pH响应作为转导信号。该项目将把研究与研究生和本科教育结合起来，并扩展到K-12学生。PI是一位在学院和大学级别屡获殊荣的教师，他将从这项研究中开发模块和案例研究，以影响他每年教的约100名新生，约30名大三学生和约20名研究生。对自组装和薄膜感兴趣的本科生将被引导到进一步的分子基础课程，包括PI自己的化学工程分子方面课程，以及每年在该项目中资助的两个本科生研究职位。PI正在开发一门关于纳米技术的课程，他将于2007年7月通过范德比尔特大学的天才教育暑期学院（SAGE）向高中二年级和三年级的学生讲授这门课程，并在每年夏天继续授课。本研究中的例子将提供动手设计项目，以增强这些聪明的年轻学生的分子直觉。此外，每年夏天，PI将继续通过校园nsf资助的教师研究经验项目，在他的小组中接待一名高中教师

Proposal Number: CBET: 0731168 Principal Investigator: G. Kane JenningsUniversity/Institution: Vanderbilt UniversityTitle: Linear and Side-Functionalized Macromolecular Adsorbates for Enhanced Versatility in the Self-Assembly at Surfaces This project will develop two classes of thiol-terminated macromolecular adsorbates for self-assembly of molecularly thick films with unique properties onto metal surfaces. One class of thiols consists of linear polymethylene with various termini, including alkyl, perfluoroalkyl, and methoxy-terminated oligo(ethylene glycol) groups. Another class consists of a polymethylene tether that contains randomly distributed functional side chains, including carboxylic acid, ester, and nonpolar groups, along with alkyl termini. These novel macromolecular adsorbates will be prepared by polyhomologation, a highly controlled polymerization that yields nearly monodisperse, long-chain alcohols with controlled length and side chain composition that can be converted to thiols to enable chemisorption at different metal surfaces. These unique adsorbates will be investigated for applications in ultra-fast and -sensitive pH-responsive thin films and 3-D monolayer templates for patterning and for entrapment and orientation of a key integral membrane protein. Intellectual Merit. The project will generate two new classes of thiol adsorbates and will demonstrate how precise macromolecular control over architecture and composition can be combined with molecular self-assembly to prepare innovative new materials. The linear class of adsorbates is expected to yield the thickest and most protective class of monolayer films yet prepared and will be used to prepare templates for etching, deposition, and biomolecule entrapment and orientation. The branched class of adsorbates should enable a tailoring of monolayer crystallinity and open new applications for monolayers in areas of responsive films. A study into the assembly of these long-chain adsorbates will yield fundamental insight into the roles of adsorbate-adsorbate interactions, including hydrogen bonding and electrostatic repulsion, and solvent-adsorbate interactions during molecular film formation. We expect the films prepared from these adsorbates to define new standards of stability, barrier performance, and versatility while presenting technologically important surfaces that can be selected as either low-energy or biologically inert. Broader Impacts. The proposed films are primed for key applications in chemical sensors, protective barrier layers against corrosion or etching, and unique templates to promote protein orientation at surfaces. Films that respond to local pH are useful in signaling the presence of analyte compounds when bound by immobilized enzymes or other receptors. For commercial relevance in sensing, the film must exhibit a large, rapid, and sharp response. Due to their hydrophobicity, thinness, and tailored composition, the proposed films with dilute carboxyl side groups should yield the largest, fastest, and sharpest response to pH of any organic film prepared to date. Such high performance would create opportunities for commercial development of these monolayers in chemical sensors where a pH response serves as the transduction signal. The project will integrate research with graduate and undergraduate education as well as outreach to K-12 students. The PI is an award-winning teacher at the School and University levels, and he will develop modules and case studies from this research to impact the ~100 freshmen, ~30 juniors, and ~20 graduate students he teaches each year. Undergraduate students who show interest in self-assembly and thin films will be steered toward further molecular-based coursework, including the PI's own Molecular Aspects of Chemical Engineering course, as well as the two undergraduate research positions funded per year within the project. The PI is developing a course on Nanotechnology that he will teach to high school sophomores and juniors through the Summer Academy for Gifted Education (SAGE) at Vanderbilt in July of 2007 and continuing each summer. Examples from this research will provide hands-on design projects to enhance the molecular intuition of these bright young students. In addition, the PI will continue to host a high school teacher in his group each summer through the on-campus NSF-funded Research Experiences for Teachers program