Separation and enrichment of platelets in blood plasma play a major role in monitoring the human health condition and transfusion purposes. Although centrifugation is frequently employed to achieve platelet separation, recent advancements in the field of cell separation place microfluidic platforms in advantageous positions over the conventional ones. In this work, we report the development of a PDMS-based passive microfluidics device to separate and enrich platelets in blood plasma. The devices were tested with whole blood in a practically relevant flow rate range of 0.2–0.6 mL/min. One of our proposed devices, comprising gradual constriction–expansion, is able to separate and enrich platelets with 8.7-fold enrichment factor, 25.5% purity, and with minimum activation at a flow rate of 0.4 mL/min using whole human blood. The amount of enrichment and purity is found to be sensitive to the ratio of RBCs and WBCs to platelets in the incoming sample. The ability of the microdevice to handle whole blood at a high flow rate, and enrich platelets in plasma with minimal activation, makes the microdevice unique. These results also demonstrate the strong effect of the RBCs and WBCs to platelet ratio on the amount of enrichment and purity that can be obtained from passive microdevices.

中文翻译：

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使用基于PDMS的被动微设备从全血中分离和富集血小板

血浆中血小板的分离和富集在监测人类健康状况和输血目的中起着重要作用。尽管经常使用离心来实现血小板分离，但是细胞分离领域的最新进展使微流体平台处于比常规平台更有利的位置。在这项工作中，我们报告了基于PDMS的被动微流控设备的发展，该设备可以分离和富集血浆中的血小板。使用全血以实际相关的0.2-0.6 mL / min的流速对设备进行测试。我们提出的一种设备，包括逐渐收缩和扩张，能够使用全血分离并富集8.7倍富集因子，25.5％纯度的血小板，并以0.4 mL / min的最小活化速度进行分离。发现富集和纯度的数量对进样中RBC和WBC与血小板的比例敏感。微型设备能够以高流速处理全血，并以最小的激活富集血浆中的血小板，这使微型设备独树一帜。这些结果还表明，RBC和WBC与血小板的比例对可从被动微型设备获得的富集量和纯度有很强的影响。