Collaborative Research: Understanding UV Protective Mechanisms Using Hybrid Nanoarchitectures

合作研究：利用混合纳米结构了解紫外线防护机制

• 批准号: 0756600
• 负责人: Anubhav Tripathi
• 金额: $ 13.75万
• 依托单位: Brown University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-01 至 2012-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0756600&HistoricalAwards=false
• 关键词: Collaborative; Research; Understanding; UV; Protective

CBET-0756600TripathiThe central hypothesis of the proposal is that the interactions, at different length scales, between a bioderived active species and various components of a protective nanoarchitecture can lead to significantly increased stability of the active species to UV exposure and oxygen. New hybrid architectures, incorporating synthetic polymers, nanoparticles, and natural dyes or DNA, must be explored to achieve tunable functional properties and to elucidate the relationship between the spatial distribution of protectant molecules (UV absorbers and UV stabilizers) and stabilization efficiency, in the context of the distance and time scales of molecular reorientation and photochemical and diffusive processes. While encapsulation techniques may have shown increases in the thermal and photo-oxidative stability of a UV sensitive material, their use in practical applications is nonexistent due to small gains. Here, we propose a new paradigm for designing protectant materials. To accomplish this objective, we propose development of three novel architectures for protectant materials. Furthermore, we propose a synergistic approach that leverages the strengths of all four PI's by combining experiments and modeling to develop a clear understanding of the mechanism by which polymeric encapsulation improves the photostability of ultraviolet (UV) sensitive materials. Intellectual Merit: The intellectual merit of the program is manifested in the goals of the project that include: (1) Development of core-shell microspheres with tunable protection properties including shell composition and thickness and degree of nanoencapsulation. The design of a new set of modular nanoarchitectures highlights the spatial arrangement of protectant molecules which can be systematically varied and the inhibition efficiency which can be monitored. (2) Development of a controlled microfluidic fabrication method where UV absorbers are integrated into the shell. (3) Novel synthesis routes for the precise production of unique nanoarchitectures encapsulating two complementary active agents: UV sensitive species and UV absorbing substances. (4) Development of transport and molecular modeling to analyze experimental results and to predict the spatial dependence of stabilization for combinations of photostabilizers. The development of synthesis routes and identification of the critical properties for efficient UV protection will help to clarify the interplay of UV protective interactions at various length scales, ranging from the molecular scale to the microscale. This research can guide the development of multifunctional protective materials into future photochemical and environmental technology in the areas of UV protection of sensitive equipment, storage and transport systems for UV sensitive reagents (e.g. biosensing reagents), thereby extending the operational life time of biological and chemical decontamination and protection technologies by preserving molecular structure and therefore function. The research is aimed at understanding how to obtain several advantageous design properties simultaneously, compared with conventional materials, such as transparency with UV-protection, control of oxygen permeation, increased thermal stability, & mechanical integrity. Integrating the outreach programs of several institutions, the proposed collaboration plans to use the experimental methods and outcomes of research as powerful educational tools for graduate, undergraduate and high school students. We propose to develop an educational program that demonstrates key features of reactive processing, nanotechnology, polymer science, and microfluidics for high school and undergraduate students, with the goal of raising and maintaining their interest in science and engineering. Also, we will integrate this research into a semester-long course and a short course for graduate students and participants from local industries. The project will utilize the research expertise of chemists and chemical engineers from Columbia University, Brown University, the University of Massachusetts at Dartmouth, and the U.S. Army Natick Research Center.

CBET-0756600 Tripathi该提案的中心假设是，生物衍生的活性物质与保护性纳米结构的各种组分之间在不同长度尺度上的相互作用可以导致活性物质对紫外线暴露和氧气的稳定性显着增加。新的混合架构，将合成聚合物，纳米粒子，天然染料或DNA，必须探索实现可调的功能特性，并阐明保护剂分子（紫外线吸收剂和紫外线稳定剂）的空间分布和稳定效率之间的关系，在分子重新取向和光化学和扩散过程的距离和时间尺度的背景下。虽然封装技术可能已经显示出UV敏感材料的热和光氧化稳定性的增加，但是由于小的增益，它们在实际应用中的使用是不存在的。在这里，我们提出了一个新的范式设计保护材料。为了实现这一目标，我们提出了三种新的保护剂材料体系结构的发展。此外，我们提出了一种协同的方法，利用所有四个PI的优势相结合的实验和建模，以开发一个清晰的理解的机制，聚合物封装提高紫外线（UV）敏感材料的光稳定性。智力优势：该计划的智力价值体现在该项目的目标中，包括：（1）开发具有可调保护性能的核壳微球，包括壳成分和厚度以及纳米封装程度。一组新的模块化纳米结构的设计突出了可以系统地改变的保护剂分子的空间排列和可以监测的抑制效率。(2)开发了一种可控的微流体制造方法，其中紫外线吸收剂被集成到外壳中。(3)用于精确生产独特纳米结构的新型合成路线，该纳米结构封装了两种互补活性剂：UV敏感物质和UV吸收物质。(4)发展运输和分子建模，分析实验结果，预测光稳定剂组合的稳定性的空间依赖性。有效的紫外线防护的关键性能的合成路线和识别的发展将有助于澄清紫外线防护相互作用在各种长度尺度，从分子尺度到微观尺度的相互作用。这项研究可以指导多功能防护材料的开发，用于未来的光化学和环境技术，如敏感设备的紫外线防护、紫外线敏感试剂（如生物传感试剂）的储存和运输系统，从而通过保留分子结构和功能来延长生物和化学去污和防护技术的使用寿命。该研究的目的是了解如何同时获得几个有利的设计性能，与传统材料相比，如具有紫外线保护的透明度，氧气渗透的控制，增加的热稳定性，机械完整性。整合了几个机构的推广计划，拟议的合作计划使用实验方法和研究成果作为研究生，本科生和高中生的强大教育工具。我们建议开发一个教育计划，展示反应处理，纳米技术，聚合物科学和微流体的高中和本科生的关键特征，提高和保持他们对科学和工程的兴趣的目标。此外，我们将把这项研究纳入一个学期的课程和短期课程的研究生和参与者从当地产业。该项目将利用来自哥伦比亚大学、布朗大学、达特茅斯的马萨诸塞州大学和美国陆军纳蒂克研究中心的化学家和化学工程师的研究专长。