CAREER: Understanding Dielectrophoretic Molecular Transport

很少有小规模分离方法可用于支持医疗诊断或稀释化学品传感等关键应用。介电分子运输（Dielectrophoretic molecular transport， DMT）可以在小尺度上灵活地将大多数溶质从水中分离出来，但由于目前的数学模型无法准确预测其行为，因此没有得到应用。这个CAREER项目旨在开发和验证DMT平衡和运输行为的模型。这些模型以及本项目将产生的对DMT的更好理解将使其得以使用，并可能导致例如芯片实验室诊断，从而扩大获得重要医疗检查的机会并改善福祉。该项目将实现这一目标，同时为研究生教育创造一个公平和包容的渠道，扩大和加强对科学研究的参与。本CAREER项目的主要研究目标是开发和验证介电分子运输（DMT）模型。为了实现这一目标，一种带有透明电极和绝缘的微流体装置已经开发出来，可以实时、空间分辨光谱测量电极之间和周围的溶液组成，同时控制初始浓度、场强和梯度以及流速。空间和时间分辨浓度数据将用于开发、改进和验证场相关活度系数的数学模型，该模型将用于预测复杂溶液中的平衡状态和耦合输运。这些不仅将构成DMT的第一个精确模型，而且还将通过评估结构-场相互作用的重要性来扩展我们对这种输运现象的理解。与这个研究项目相结合的是一个以研究为导向的本科生替代高级设计，这将引导学生从开始一个研究项目到创造和传播研究成果。本职业计划书的研究部分将作为核心，保证学生在课程内的研究机会。将研究和指导结合到熟悉的课堂环境中，大大减少了文化和制度障碍，同时减少了与本科生研究相关的不确定性和时间成本。这样，该计划将增加本科生研究的参与，并使学生在未来的教育和职业生涯中继续茁壮成长。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Few small-scale separation methods are available to support critical applications like medical diagnostics or the sensing of dilute chemicals. Dielectrophoretic molecular transport (DMT), which works at small length scales, flexibly separates most solutes out of water but it is not used because current mathematical models are unable to accurately predict its behavior. This CAREER project seeks to develop and validate models of DMT equilibrium and transport behavior. These models and the improved understanding of DMT that will result from this project will enable its use and could result in, for example, lab-on-a-chip diagnostics which broaden access to important medical tests and improve well-being. This project will accomplish this while creating an equitable and inclusive pipeline to graduate education that will broaden and strengthen participation in scientific research.The primary research goal of this CAREER project is to develop and validate models for dielectrophoretic molecular transport (DMT). To accomplish this objective, a microfluidic device with transparent electrodes and insulation has been developed that permits real time, spatially resolved spectroscopy measurements of solution composition between and around electrodes while controlling initial concentrations, field strengths and gradients, and flow rates. Spatially and temporally resolved concentration data will be used to develop, improve, and validate mathematical models of field-dependent activity coefficients, which will be used to predict equilibrium states and coupled transport in complex solutions. Not only will these constitute the first accurate models of DMT but will also expand our understanding of this transport phenomenon by assessing the importance of structure-field interactions. Integrated with this research project is an undergraduate, research-oriented alternative to Senior Design, which will lead students from starting a research project through to creating and disseminating research products. The research component of this CAREER proposal will serve as a core, guaranteed research opportunity for students within the course. Incorporating research and mentoring into a familiar classroom setting significantly reduces cultural and institutional barriers while reducing uncertainty and time cost associated with undergraduate research. In doing so, this plan will increase participation in undergraduate research and ideally position students to continue and thrive in their future education and career.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.