Automated generation of a thin blood smear with a pumpless, capillary-driven, microfluidic would overcome the limitations of manually prepared smears and enable potential point-of-care (POC) applications. Herein, this was accomplished with microfluidic design that leveraged an amphiphilic silicone and channel pillars. The silicone (Sylgard 184) was combined with a surface-modifying additive (SMA), an amphiphilic poly(ethylene oxide) (PEO)-silane at varying concentrations (3, 5, and 7 wt%). The channels were formed with dimensions of 4.7 µm, 250 µm, and 16 mm (height × width × length, respectively). Pillar sections were added at the inlet, outlet and two interior sections to not only prevent channel collapse but to improve flow and cell distribution. After deposition of blood (0.3, 1, and 2 µL) to the channel inlet, the flow time and flow stop times were recorded and the channels imaged to assess smear uniformity and for automated cell counting. A thin blood smear was generated for microfluidic chips prepared with 5 wt% SMA and provided with 0.3 µL of blood.

使用无泵、毛细管驱动的微流体自动生成薄血涂片将克服手动制备的涂片的局限性，并实现潜在的即时 (POC) 应用。在这里，这是通过利用两亲硅胶和通道柱的微流体设计来实现的。将有机硅 (Sylgard 184) 与表面改性添加剂 (SMA)、不同浓度（3、5 和 7 wt%）的两亲性聚（环氧乙烷）（PEO）-硅烷混合。形成的通道尺寸分别为 4.7 µm、250 µm 和 16 mm（高 × 宽 × 长）。在入口、出口和两个内部部分添加了支柱部分，不仅可以防止通道塌陷，还可以改善流动和细胞分布。将血液（0.3、1 和 2 µL）沉积到通道入口后，记录流动时间和流动停止时间，并对通道成像以评估涂片均匀性和自动细胞计数。为用 5 wt% SMA 制备的微流控芯片生成薄血涂片，并提供 0.3 µL 血液。