Collaborative Research: Actively Controllable Microfluidics with Film-Confined Redox-Magnetohydrodynamics: experiment and simulation

Fritch/Isaac1336853/1336722将研究氧化还原聚合物修饰电极在小体积磁场中的选择性激活，以在空间和时间上控制微流体。这种新形式的磁流体动力学(MHD)，与在溶液中添加氧化还原物种或根本不添加它们相反，克服了阻碍MHD在芯片实验室(LOAC)设备中使用的问题。它允许更高的电流和更低的电压，因此，更高的磁流体力和更快的速度，不会形成气泡或腐蚀，更快的响应时间，以及与检测器和样品的兼容性。与其他微泵相比，MHD提供了更多的通用性，因为无需重新设计设备的通道就可以对流量进行编程。化学和生物化学方面的研究人员在大学进行的跨学科、预先存在的合作。在阿肯色州大学和密苏里州大学攻读机械与航天工程专业。科学与技术部将进行这项研究。智能优点：电极上限制在聚合物膜上的化学物种的还原/氧化在溶液中产生离子电流。当与磁场成直角时，产生的磁流体力会导致流体在第三维空间中流动。可单独寻址的电极将被制造成所需的图案，聚合物薄膜将被聚合并通过电化学进行表征，电极将被磁场中的电流和电压激活，流动将通过微珠在溶液中的运动来监测。其目的是(1)建立电极上氧化还原聚合物膜的大库仑容量、快速响应和等效电路模型，(2)使用垂直于磁场的氧化还原聚合物修饰电极的同心圆盘-环结构来控制和最大化流速、调谐轮廓、切换方向和驱动相邻的逆流，(3)通过对氧化还原聚合物膜进行再充电来维持流体流动，以及(4)使用模拟来获得离子电流密度、磁流体力密度和流体速度随时间的空间图，与实验相比，并评估超过实验极限的参数，以更好地设计氧化还原磁流体微流控装置。广泛的影响：目标是以可编程的方式控制微流控，对公众感兴趣的产品产生深远的影响，例如用于医疗、环境和家庭用途的手持、独立的化学分析装置。该项目的跨学科性质加强了对参与研究的学生的培训。完成的软件模块将免费提供给科学界进行测试和进一步评估。新学校的科学、数学和语言艺术教师与密苏里大学和密苏里大学S&T的导师之间的外展合作将以MHD为起点，刺激中学生对力和能量主题的病毒式学习。学生将与老师和导师合作进行自我指导的项目，使用他们自己的词汇和视角通过视频交流结果，他们已经编写、编辑、制作了这些视频，并将其发布在互联网上供公众观看和评论。这一方法有望弥合大学研究和中学教育之间的差距，同时加强STEM教育和教育工作者的发展，并提高公众的科学素养和公众对科学技术的参与。

Fritch/Isaac1336853/1336722Selective activation of redox-polymer-modified electrodes in a small volume in magnetic fields will be investigated to control microfluidics spatially and temporally. This new form of magnetohydrodynamics (MHD), as opposed to adding redox species to the solution or not adding them at all, defeats problems that hinder MHD from use in lab-on-a-chip (LOAC) devices. It allows higher currents with lower voltages, and thus, higher MHD forces and faster velocities without bubble formation or corrosion, faster response times, and compatibility with detectors and samples. MHD offers greater versatility over other micropumps, because flow can be programmed without redesigning channels of a device. An interdisciplinary, preexisting collaboration of investigators in Chemistry & Biochemistry at the Univ. of Arkansas and in Mechanical & Aerospace Engineering at Missouri Univ. of Science & Technology will perform the research.Intellectual Merit :Reduction/oxidation of chemical species confined to polymer films on electrodes creates an ionic current in solution. When at right angles to the magnetic field, the resulting MHD force causes fluid to flow there in the third dimension. Individually-addressable electrodes will be fabricated in desired patterns, polymer films will be polymerized and characterized by electrochemistry, electrodes will be activated with current and voltage in magnetic fields, and flow will be monitored by microbead movement in solution. The objectives are to (1) establish large coulombic capacity, fast response, and equivalent circuit models for redox-polymer films on electrodes, (2) control and maximize flow velocities, tune profiles, switch direction, and drive adjacent counter-flows using concentric disk-ring configurations of redox-polymer-modified electrodes perpendicular to a magnetic field, (3) sustain fluid flow by recharging redox-polymer films, and (4) use simulations to obtain spatial maps of ionic current density, MHD force density, and fluid velocities as a function of time, compare with experiment, and evaluate parameters that exceed experimental limits to better design redox-MHD microfluidic devices.Broader Impacts :The goal is to control microfluidics in a programmable way with far-reaching consequences toward products of interest to the public, such as hand-held, self-contained chemical analysis units for medical, environmental, and household uses. The interdisciplinary nature of the project enhances training of students involved in the research. Completed software modules will become available for testing and further evaluation to the scientific community free of charge. An outreach collaboration between science, math, and language arts teachers at The New School and mentors at the U of A and Missouri S&T will use MHD as a starting point to stimulate viral learning for middle school students on topics of forces and energy. Students will perform self-directed projects in collaboration with teachers and mentors, communicate results with videos using their own vocabulary and perspective, which they have scripted, edited, produced, and post them on the internet for public viewing and commentary. This approach is expected to bridge the gap between university research and middle school education, while simultaneously enhancing STEM education and educator development and increasing public scientific literacy and public engagement with science and technology.