Charge and size based filtration by ultrathin silicon membranes

通过超薄硅膜进行基于电荷和尺寸的过滤

• 批准号: 7278551
• 负责人: James L McGrath
• 金额: $ 17.63万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7278551
• 关键词: Address; Adsorption; Albumins; Bioreactors; Biosensor; Buffers; Cell Membrane Permeability; Charge; Chemicals; Clinical; Complex; Data; Devices; Diagnostic; Dialysis procedure; Diffusion; Dyes; Electrons; Facility Construction Funding Category; Filtration; Fluorescent Dyes; Goals; Gold; Ionic Strengths; Isoelectric Point; Kinetics; Libraries; Measures; Membrane; Metals; Microfluidic Microchips; Microfluidics; Modeling; Modification; Molecular; Names; Nanosphere; Oxides; Performance; Permeability; Physical Dialysis; Platinum; Polyethylene Glycols; Porosity; Preclinical Drug Evaluation; Proteins; Range; Rate; Sampling; Screening procedure; Silicon; Solutions; Source; Surface; System; Therapeutic; Time; Transmembrane Transport; Transmission Electron Microscopy; Work; aerobic respiration control protein; base; improved; macromolecule; micro-total analysis system; novel; particle; protein transport; research study; size; solute; theories; transmission process; voltage

DESCRIPTION (provided by applicant): This work will investigate the potential of a nanoporous silicon membrane (pnc-Si) to provide revolutionary filtration of macromolecules based on their size and charge. Because the novel membrane material is molecularly thin (15 nm), it is predicted to improve the efficiency of both diffusion and convective flow based separations. Because the material is made from silicon, manufacturing is scalable, readily integrated into microfluidic devices, and amenable to surface modifications could make membrane permeability controllable through an externally controlled voltage. The material may enable a host of small scale analytical, preparative and therapeutic devices. Aim 1: Quantitatively characterize the performance of pnc-Si membranes for diffusion- based separations we will quantify the function of pnc-Si membranes in diffusion-based separations. Using a membrane library with a range of porosities and pore sizes, we will determine: 1) rejection sizes of model species and protein mixtures; and 2) the mobility of small solutes, model particles, and proteins through pnc-Si membranes. Work will directly address the potential deleterious effects of protein adsorption by measuring small solute transport in the presence and absence of high protein concentrations. Membranes will be directly inspected for evidence of bio-fouling by transmission electron microscopy. If protein adsorption slows transport, membranes will be modified by grafting with short PEG molecules, and the modified membranes re-characterized. Aim 2: Quantitatively characterize pnc-Si membranes for charged-based separations Here we will characterize the ability of pnc-Si membranes to separate macromolecules based on charge. We will measure diffusive transport of charged dyes in solutions of different ionic strength. We will quantify results using as-prepared membranes and membranes that we modify to carry permanent negative or positive charge, Results will be interpreted in the context of Debye-Huckel theory. We will then examine the importance of membrane charge on protein transport by modulating solution pH around the isoelectric point of albumin. Finally, will coat pnc-Si membranes with noble metals with the goal of actively adjusting membrane permeability through external control over membrane charge. This project will characterize the ability of a new silicon-based, nanoporous membrane to selectively filter macromolecules based on size and charge. The molecularly thin nanomembranes have the potential to revolutionize filtration rates and are the first filter material that can be integrated into microfluid systems as modules. These abilities are expected to enable a host of new small scale clinical and diagnostic devices.

描述（由申请人提供）：这项工作将研究纳米孔硅膜（PNC-SI）的潜力，以根据其大小和电荷来提供大分子的革命性过滤。由于新型的膜材料是分子薄（15 nm），因此预计它将提高扩散和基于对流的基于流动的分离的效率。由于材料是由硅制成的，因此制造是可扩展的，很容易整合到微流体设备中，并且可以通过外部控制的电压来控制膜渗透率。该材料可以实现大量的小规模分析，制备和治疗设备。 AIM 1：定量表征PNC-SI膜在基于扩散的分离中的性能，我们将量化PNC-SI膜在基于扩散的分离中的功能。使用具有多种孔隙和孔径的膜文库，我们将确定：1）模型物种和蛋白质混合物的排斥大小； 2）小溶质，模型颗粒和蛋白质通过PNC-SI膜的迁移率。工作将直接通过在存在和不存在高蛋白质浓度的情况下测量小溶质转运来直接解决蛋白质吸附的潜在有害作用。将直接检查膜的透射电子显微镜生物污染证据。如果蛋白质吸附速度降低了传输，则将通过用短PEG分子接枝而修饰膜，并重新征服修饰的膜。 AIM 2：定量表征PNC-SI膜的基于带电的分离，我们将表征PNC-SI膜根据电荷分离大分子的能力。我们将测量带电染料在不同离子强度溶液中的扩散运输。我们将使用经过准备的膜和膜来量化结果，并在Debye-Huckel理论的背景下解释结果，以携带永久性负电荷或正电荷。然后，我们将通过调节白蛋白的等电点调节溶液pH来检查膜电荷对蛋白质转运的重要性。最后，将用高尚的金属涂上PNC-SI膜，目的是通过对膜电荷的外部控制来积极调节膜渗透率。该项目将表征新的基于硅的纳米多孔膜根据大小和电荷选择性过滤大分子的能力。分子薄的纳米膜具有革命性过滤速率的潜力，并且是可以将其作为模块集成到微流体系统中的第一个过滤材料。这些能力有望实现许多新的小型临床和诊断设备。