A Microfluidic Protein Separation Device Based on Dielectrophoresis

一种基于介电泳的微流控蛋白质分离装置

• 批准号: 7944203
• 负责人: Alexandra Ros
• 金额: $ 18.14万
• 依托单位: ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7944203
• 关键词: Address; Adsorption; Alzheimer' s Disease; Amyloid; Amyloid beta-Protein; Automobile Driving; Behavior; Biological Assay; Biomedical Research; Body Fluids; Cerebrospinal Fluid; Charge; Clinical; Complement; Complex; Complex Mixtures; Computer Simulation; Coupled; Detection; Development; Device or Instrument Development; Devices; Diagnosis; Disease Marker; Elements; Gel; Goals; Immunoglobulin Fragments; Injection of therapeutic agent; Investigation; Ionic Strengths; Laboratories; Laws; Malignant - descriptor; Measurement; Methods; Microfluidic Microchips; Microfluidics; Modeling; Molecular Conformation; Molecular Weight; Motion; Nature; Operative Surgical Procedures; Pathway interactions; Peptides; Periodicity; Protein Analysis; Proteins; Recovery; Sample Size; Sampling; Shapes; Site; Solutions; Structure; Surface; System; Techniques; Testing; Time; Variant; base; density; design; electric field; immunoreaction; insight; interest; micro-total analysis system; novel; novel diagnostics; point-of-care diagnostics; prevent; public health relevance; rapid diagnosis; response; single cell analysis; tool

DESCRIPTION (provided by applicant): Reliable and rapid separation of proteins is both a fundamental and challenging problem for bioanalytical and biomedical research. Conventional separation techniques reach their limits at extremes, for example, when increased sample complexity demands for the analysis of relevant disease markers in extremely small concentration and within a huge background. Problems further arise for time critical samples, i.e. when rapid answers are required, such as for samples with temporally degrading or altering composition or when rapid diagnosis is essential, such as during surgery. These limitations can be more drastic for smaller sample volumes and concomitantly low amount of proteins, such as in the case of minimal invasive diagnosis or single cell analysis. The latter is specifically important for understanding specific cellular pathways and malignant progressions, which would otherwise be averaged in the ensemble measurement. Another extremely relevant example represents the diagnosis of Alzheimer's Disease, which is particularly challenging due to the transient nature of the involved peptide species and their extremely low abundance in body fluids. This exploratory proposal aims to develop dielectrophoretic devices for the efficient, rapid and gel-free separation, purification and pre-concentration of proteins on microfluidic platforms. This project applies a new principle for the gel-free separation of proteins in microfluidic systems. It exploits dielectrophoresis (DEP) of proteins, which as polarizable objects respond to a non-uniform electric field with a migrational motion. As the polarizability depends on various parameters such as shape, charge, charge density, permittivity or deformability it thus allows probing the DEP response of proteins in a broad range. The dielectrophoretic response of proteins is provoked in tailored microstructure designs on a lab-on- a-chip platform in which the necessary inhomogeneous electric field gradient can be optimally generated. A fundamental investigation of the DEP behavior of selected proteins will give insight into the necessary electrical driving parameters and reveal optimized conditions for more complex separation problems as well as the purification and pre-concentration of proteins and peptides. This novel device is capable of analyzing protein samples in time scales of a few minutes and reduces sample volumes to the pL-nL range. In particular, we develop a combined microfluidic immunoaffinity and DEP based separation assay for beta-amyloid (A2) oligomers in cerebrospinal fluid. This novel DEP separation method thus represents a development of outstanding importance for biomedical research and point of care diagnostics. PUBLIC HEALTH RELEVANCE (provided by the applicant): The goal of this project is to design and test devices for fast, reliable and gel-free protein separation and pre-concentration based on dielectrophoresis on a microfluidic platform. The development of these devices extends current separation techniques at their limits, i.e. for low sample concentration, time critical analyzes, miniature sample amounts and complex samples. It will facilitate biomedical research and eventually clinical laboratory practice, in particular, rapid and on-site point of care diagnostics.

描述（由申请人提供）：可靠且快速的蛋白质分离对于生物分析和生物医学研究来说既是一个基本问题又是一个具有挑战性的问题。传统的分离技术在极端情况下达到了极限，例如，当样品复杂性增加时，需要在极小的浓度和巨大的背景下分析相关疾病标记物。对于时间关键的样品，即当需要快速回答时，例如对于成分暂时降解或改变的样品，或者当快速诊断是必要的时，例如在手术期间，还会出现问题。对于较小的样本量和随之而来的蛋白质含量较低，例如在微创诊断或单细胞分析的情况下，这些限制可能更加严重。后者对于理解特定的细胞途径和恶性进展特别重要，否则将在整体测量中进行平均。另一个极其相关的例子是阿尔茨海默氏病的诊断，由于所涉及的肽种类的短暂性及其在体液中的丰度极低，该诊断特别具有挑战性。该探索性提案旨在开发介电泳装置，用于在微流体平台上高效、快速、无凝胶地分离、纯化和预浓缩蛋白质。该项目应用了微流体系统中蛋白质无凝胶分离的新原理。它利用蛋白质的介电泳 (DEP)，作为可极化物体，蛋白质会通过迁移运动响应非均匀电场。由于极化率取决于各种参数，例如形状、电荷、电荷密度、介电常数或变形能力，因此可以在广泛的范围内探测蛋白质的 DEP 响应。芯片实验室平台上的定制微结构设计可以激发蛋白质的介电泳响应，在该平台上可以优化地生成必要的不均匀电场梯度。对选定蛋白质的 DEP 行为进行基础研究将深入了解必要的电驱动参数，并揭示更复杂的分离问题以及蛋白质和肽的纯化和预浓缩的优化条件。这种新颖的设备能够在几分钟的时间内分析蛋白质样品，并将样品体积减少到 pL-nL 范围。特别是，我们开发了一种基于微流体免疫亲和和 DEP 的组合分离测定法，用于检测脑脊液中的 β-淀粉样蛋白 (A2) 寡聚物。因此，这种新颖的 DEP 分离方法代表了对生物医学研究和护理诊断具有突出重要性的发展。 公共健康相关性（由申请人提供）：该项目的目标是设计和测试基于微流体平台上的介电泳的快速、可靠和无凝胶蛋白质分离和预浓缩的装置。这些设备的开发扩展了当前分离技术的极限，即低样品浓度、时间关键分析、微型样品量和复杂样品。它将促进生物医学研究并最终促进临床实验室实践，特别是快速现场护理诊断。