Dielectrophoretic Particle Chromatography (DPC) with scalable separation effect at preparative scale

介电泳颗粒色谱 (DPC) 在制备规模上具有可扩展的分离效果

• 批准号: 382065007
• 负责人: Dr. Michael Baune, since 7/2022
• 金额: --
• 依托单位: School of Chemical and Bioprocess Engineering
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/382065007?language=en
• 关键词: Dielectrophoretic; Particle; Chromatography; DPC; scalable

The separation of micron and submicron particles from a liquid medium or their fractionation according to specific properties is essential for a variety of applications. Particle separation is key, for instance, in (bio-) analytics, medical diagnostic, material recycling, product quality enhancement, or to improve the cost efficiency of industrial processes. As an example, to recover precious metals from scrap, the scrap is firstly milled to produce smaller pieces that could be separated with standard methods according to density, magnetism, or other properties. Most of the precious metal, however, is concentrated in the fine dust that is produced as a byproduct and which is too small for an effective fractionation. Standard methods to sort such small submicron or micro particles are for example gel electrophoresis or size exclusion chromatography. These methods, however, can only process small quantities per batch and the recovery of the resulting fractions is intensive in both cost and time. This effectively limits those techniques to analytical application. Other continuous fractionation approaches for higher throughputs, such as field flow fractionation or centrifugation lose both selectivity and efficiency when processing particles smaller than 10 µm. Here, dielectrophoretic particle chromatography is introduced. This methods uses dielectrophoresis, an ac electrokinetic effect, to increase the residence time of target particles according to specific properties in a chromatography column: Particle mixtures will interact with a superimposed inhomogeneous ac electric field differently according to their polarizability, which is a particle property that depends on particle form, size and material. The inhomogeneous ac field is created by two concentric electrodes which form an annulus. The annulus is filled with a dielectric packed-bed (e.g., of quartz spheres) that scatters the electric field of the concentric electrodes and creates local inhomogeneities. Such an arrangement allows for several orders of magnitude higher throughput compared to conventional microfluidic dielectrophoretic separators. The applied ac field is modulated in its frequency in order to target specific differences in the frequency-dependent particle polarizability. To better understand the underlying transport mechanisms and to design a dielectrophoretic chromatography column that can operate at industrially relevant throughputs, both microchannels as well as macroscopic packed-bed columns will be investigated. A detailed parameter variation study (regarding applied field strength, frequency, packing and channel geometry, as well as modulation frequency) will be conducted using both simulation and experimental methods. Aim of this project is the implementation of a dielectrophoretic chromatography column for a continuous multi-dimensional fractionation of particles in the liquid phase at throughputs of up to 10 g per hour.

从液体介质中分离微米和亚微米颗粒或根据其特定性质对其进行分选对于各种应用都是必不可少的。颗粒分离是关键，例如，在（生物）分析，医疗诊断，材料回收，产品质量提高，或提高工业过程的成本效率。例如，为了从废料中回收贵金属，首先将废料磨成更小的碎片，这些碎片可以根据密度、磁性或其他性质用标准方法分离。然而，大部分贵金属都集中在作为副产品产生的细粉尘中，这些粉尘太小，无法进行有效的分离。分选这种小的亚微米或微颗粒的标准方法是例如凝胶电泳或尺寸排除色谱法。然而，这些方法每批只能处理少量，并且回收所得馏分在成本和时间上都是密集的。这有效地限制了这些技术的分析应用。其他用于更高通量的连续分馏方法，如场流分馏或离心，在处理小于10 μ m的颗粒时，会失去选择性和效率。这里介绍介电泳颗粒色谱法。该方法利用介电电泳，一种交流电动力学效应，根据色谱柱中的特定性质来增加目标颗粒的停留时间：颗粒混合物将根据其极化率与叠加的不均匀交流电场发生不同的相互作用，这是一种取决于颗粒形式，大小和材料的颗粒性质。非均匀交流场是由两个同心电极形成一个环空产生的。环空中充满了介质填充层（例如石英球），这分散了同心电极的电场并产生了局部不均匀性。这样的安排允许几个数量级较高的吞吐量相比，传统的微流体介电泳分离器。所施加的交流场在其频率上进行调制，以便针对频率相关粒子极化率的特定差异。为了更好地理解潜在的传输机制，并设计一种介电泳色谱柱，可以在工业相关的吞吐量下运行，微通道和宏观填充床柱都将被研究。详细的参数变化研究（关于应用场强，频率，封装和通道几何形状，以及调制频率）将使用模拟和实验方法进行。该项目的目的是实现一个介电泳色谱柱，在液相中以高达每小时10克的通量对颗粒进行连续的多维分馏。