Fluorescence activated cell sorting (FACS) has become an essential technique widely exploited in biological studies and clinical applications. However, current FACS systems are quite complex, expensive, bulky, and pose potential sample contamination and biosafety issues due to the generation of aerosols in an open environment. Microfluidic technology capable of precise cell manipulation has great potential to reinvent and miniaturize conventional FACS systems. In this work, we demonstrate a benchtop scale FACS system that makes use of a highly focused traveling surface acoustic wave beam to sort out micron-sized particles and biological cells upon fluorescence interrogation at ∼kHz rates. The highly focused acoustic wave beam has a width of ∼50 μm that enables highly accurate sorting of individual particles and cells. We have applied our acoustic FACS system to isolate fluorescently labeled MCF-7 breast cancer cells from diluted whole blood samples with the purity of sorted MCF-7 cells higher than 86%. The cell viability before and after acoustic sorting is higher than 95%, indicating excellent biocompatibility that should enable a variety of cell sorting applications in biomedical research.

中文翻译：

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通过聚焦的行进表面声束对荧光激活的细胞进行分选

荧光激活细胞分选（FACS）已成为在生物学研究和临床应用中广泛使用的一项必不可少的技术。然而，当前的FACS系统非常复杂，昂贵，笨重，并且由于在开放环境中产生气溶胶而引起潜在的样品污染和生物安全问题。能够精确控制细胞的微流体技术具有巨大的潜力，可以重新发明和最小化传统的FACS系统。在这项工作中，我们展示了台式规模的FACS系统，该系统利用高度聚焦的行进表面声波束，以〜kHz的频率进行荧光询问，从而可以分离出微米级的颗粒和生物细胞。高聚焦声波束的宽度约为50μm，可对单个粒子和细胞进行高度精确的分选。我们已应用声学FACS系统从稀释的全血样品中分离出荧光标记的MCF-7乳腺癌细胞，其中分选出的MCF-7细胞的纯度高于86％。声学分选之前和之后的细胞存活率均高于95％，表明具有出色的生物相容性，这应该使生物医学研究中的各种细胞分选应用成为可能。