Lab-on-chip devices are widely being used for binary and ternary cell/particle separation applications. Among the lab-on-chip methods, dielectrophoresis (DEP) is a cost-effective and label-free method, with great capabilities for size-based separation of cells and particles, which is mostly performed in sheath-assisted forms. However, the elimination of the sheath flows offers advantages such as ease of operation and higher sample throughput. In this work, we present a comparison of sheath-assisted and sheathless DEP separation of three sizes of microparticles using tilted electrodes. The sheath-assisted design was capable of separating the 5, 10, and 15 μm particles with a separation efficiency as high as 98.0% for 15 μm particles. By adding a DEP focusing region, a sheathless DEP separator was proposed, which offered higher throughputs (up to 10 times) at the cost of lowering the separation efficiency (a reduction up to 10.3% for 15 μm) compared to the sheath-assisted design. To enhance the separation efficiency, a combination of the DEP focusing accompanied by weak sheath flows from both sides was proposed. This design achieved the highest sample separation yield in the outlets (as high as 98.7% for 15 μm) with a sample throughput of more than 4.2 μL/min. This study provides insights into the choice of an appropriate platform for any application in which the yield, purity, throughput, and portability must be considered.

中文翻译：

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鞘辅助与无鞘介电泳颗粒分离

片上实验室设备广泛用于二元和三元细胞/颗粒分离应用。在芯片实验室方法中，介电泳 (DEP) 是一种具有成本效益且无标记的方法，具有很大的基于尺寸分离细胞和颗粒的能力，这主要以鞘辅助形式进行。然而，鞘流的消除提供了诸如易于操作和更高的样品通量等优点。在这项工作中，我们比较了使用倾斜电极对三种尺寸的微粒进行鞘辅助和无鞘 DEP 分离。鞘辅助设计能够分离 5、10 和 15 μm 颗粒，对于 15 μm 颗粒的分离效率高达 98.0%。通过增加一个 DEP 聚焦区域，提出了一种无鞘 DEP 分离器，与鞘辅助设计相比，它以降低分离效率（15 μm 降低高达 10.3%）为代价提供更高的通量（高达 10 倍）。为提高分离效率，提出了将 DEP 聚焦与来自两侧的弱鞘流相结合的方法。该设计在出口处实现了最高的样品分离率（15 μm 的分离率高达 98.7%），样品通量超过 4.2 μL/min。这项研究为必须考虑产量、纯度、吞吐量和便携性的任何应用选择合适的平台提供了见解。提出了DEP聚焦与两侧弱鞘流相结合的方法。该设计在出口处实现了最高的样品分离率（15 μm 的分离率高达 98.7%），样品通量超过 4.2 μL/min。这项研究为必须考虑产量、纯度、吞吐量和便携性的任何应用选择合适的平台提供了见解。提出了DEP聚焦与两侧弱鞘流相结合的方法。该设计在出口处实现了最高的样品分离率（15 μm 的分离率高达 98.7%），样品通量超过 4.2 μL/min。这项研究为必须考虑产量、纯度、吞吐量和便携性的任何应用选择合适的平台提供了见解。