CAREER: Plasmonic Nanocavities for Single Molecule Detection

职业：用于单分子检测的等离子体纳米腔

• 批准号: 0954976
• 负责人: Qihuo Wei
• 金额: $ 40万
• 依托单位: Kent State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0954976&HistoricalAwards=false
• 关键词: CAREER; Plasmonic; Nanocavities; Single; Molecule

Plasmonic Nanocavities for Single Molecule DetectionThis proposal describes an integrated research, education and outreach plan with a focus on plasmonic nanocavities and their applications in single molecule surface enhanced Raman spectroscopy (SERS). The proposed plasmonic nanocavities, or the tiny gaps between metal nanowires (Ag), are formed by stacking a second layer of parallel Ag nanowires on top of a first layer of perpendicularly oriented Ag nanowires. Preliminary studies show that when the gaps between top and bottom nanowires are reduced to a few nanometers or ten millionth of the diameter of a human hair, illuminating light can be focused into such tiny nanogaps with up to 100000 times increase in light intensity. When molecules are placed inside these plasmonic nanocavities, their Raman scattering intensity can be largely enhanced so that even single molecule signals can be observed. The Raman spectra represent unique vibration information of molecules which can be used for direct detection and identification of the molecules. The proposed research aims at developing nanofabrication processes for nanowires and nanocavities, characterization and fundamental understanding of these plasmonic nanocavities, and exploring their applications in SERS. The ultimate goal is to demonstrate a robust single molecule sensing platform based on SERS. The education plan includes implementing an educational program aimed to attract high ability students in Northeast Ohio to majors in STEM (science, technology, engineering and mathematics) fields and to provide those students already in STEM fields with mentoring and research opportunities.Intellectual merit: The Ag nanowire crossbars are unique in three aspects: (1) nanoantennas (i.e. Ag nanowire) and nanocavities are integrated in single platform, making it highly efficient to focus light into nanometer scale; (2) the vertical cavity design makes it possible to fabricate nanogaps with unprecedented accuracy by using thin film deposition techniques; (3) Molecules within these nanocavities can be addressed electrically by applying voltages through these nanowires, providing great flexibility to control the molecules and nanocavities. The proposed research will answer fundamental questions about SERS enhancement mechanisms and lead to development of reproducible single molecule sensors. Broader impact: The proposed research benefits society because single molecule sensors can find myriad applications from homeland security to disease diagnostics for healthcare. The educational and outreach components of this career plan include developing of a guided research experience program for the Post Secondary Enrollment Option Program (PSEOP) students at Kent State University (KSU); mentoring undergraduates in research; creating an outreach program called ?Parent?s Night? for high school students and their parents; enhancing graduate education through involving graduate students in multidisciplinary research, and developing curriculum for teaching nano/biomaterials at the graduate level. KSU is one of three largest public universities in the state of Ohio, over 80% KSU students are undergraduates; and KSU primarily serves low- to middle-income undergraduates. This unusual combination of institutional traits makes KSU ideally suited to recruit students from under-represented groups and/or disadvantaged communities to pursue careers in science and related fields. The proposed educational plan will have a direct impact on improving enrollment, retention, and graduation rates of under-represented group members and women in science and related fields at KSU.

等离子体纳米腔单分子检测该提案描述了一个综合的研究，教育和推广计划，重点是等离子体纳米腔及其在单分子表面增强拉曼光谱（Sers）中的应用。所提出的等离子体纳米腔，或金属纳米线（Ag）之间的微小间隙，是通过在第一层垂直取向的Ag纳米线的顶部堆叠第二层平行的Ag纳米线而形成的。初步研究表明，当上下纳米线之间的间隙减小到几纳米或人类头发直径的千万分之一时，照明光可以聚焦到这样微小的纳米间隙中，光强度增加高达10万倍。当分子被放置在这些等离子体纳米腔内部时，它们的拉曼散射强度可以大大增强，使得甚至可以观察到单分子信号。拉曼光谱代表了分子的独特振动信息，可用于分子的直接检测和鉴定。拟议的研究旨在开发纳米线和纳米腔的纳米加工工艺，表征和基本了解这些等离子体纳米腔，并探索它们在Sers中的应用。最终的目标是展示一个强大的单分子传感平台的基础上Sers。该教育计划包括实施一项教育计划，旨在吸引俄亥俄州东北部的高能力学生攻读STEM专业（科学、技术、工程和数学）领域，并为那些已经在STEM领域的学生提供指导和研究机会。智力优势：Ag纳米线交叉杆在三个方面是独一无二的：（1）纳米天线（即Ag纳米线）和纳米腔集成在单个平台中，使得将光聚焦到纳米尺度是高效的;（2）垂直腔设计使得可以通过使用薄膜沉积技术以前所未有的精度制造纳米间隙;（3）这些纳米腔中的分子可以通过经由这些纳米线施加电压来电寻址，从而提供控制分子和纳米腔的极大灵活性。这项研究将回答有关Sers增强机制的基本问题，并导致可重复的单分子传感器的发展。更广泛的影响：这项拟议中的研究对社会有益，因为单分子传感器可以找到从国土安全到医疗保健疾病诊断的无数应用。该职业计划的教育和推广部分包括为肯特州立大学（KSU）的中学后入学选择计划（PSEOP）学生制定指导研究经验计划;指导研究本科生;创建一个名为？家长？晚上？为高中生及其家长提供的信息;通过让研究生参与多学科研究来加强研究生教育，并为研究生阶段的纳米/生物材料教学开发课程。KSU是俄亥俄州三所最大的公立大学之一，超过80%的KSU学生是本科生; KSU主要服务于中低收入的本科生。这种不寻常的机构特征的组合使得KSU非常适合招收来自代表性不足的群体和/或弱势群体的学生，以追求科学和相关领域的职业生涯。拟议的教育计划将对提高入学率，保留率和代表性不足的群体成员和妇女在科学和相关领域的毕业率在KSU的直接影响。