10.1021/acs.analchem.9b03021.s002 Peixian Li Peixian Li Minhui Liang Minhui Liang Xiaoguang Lu Xiaoguang Lu Joycelyn Jia Ming Chow Joycelyn Jia Ming Chow Chrishan J. A. Ramachandra Chrishan J. A. Ramachandra Ye Ai Ye Ai Sheathless Acoustic Fluorescence Activated Cell Sorting (aFACS) with High Cell Viability American Chemical Society 2019 cell level High Cell Viability FTSAW Sheathless Acoustic Fluorescence Activated Cell MDA aFACS system recovery rate 1 μ m particles human-induced pluripotent stem-cell-derived cardiomyocytes MCF cell viability 2019-11-18 20:34:51 Media https://acs.figshare.com/articles/media/Sheathless_Acoustic_Fluorescence_Activated_Cell_Sorting_aFACS_with_High_Cell_Viability/10324451 In this work, we demonstrate a sheathless acoustic fluorescence activated cell sorting (aFACS) system by combining elasto-inertial cell focusing and highly focused traveling surface acoustic wave (FTSAW) to sort cells with high recovery rate, purity, and cell viability. The microfluidic sorting device utilizes elasto-inertial particle focusing to align cells in a single file for improving sorting accuracy and efficiency without sample dilution. Our sorting device can effectively focus 1 μm particles which represents the general minimum size for a majority of cell sorting applications. Upon the fluorescence interrogation at the single cell level, individual cells are deflected to the target outlet by a ∼50 μm wide highly focused acoustic field. We have applied our aFACS to sort three different cell lines (i.e., MCF-7, MDA-231, and human-induced pluripotent stem-cell-derived cardiomyocytes; hiPSC-CMs) at ∼kHz with a sorting purity and recovery rate both of about 90%. A further comparison demonstrates that the cell viability drops by 35–45% using a commercial FACS machine, while the cell viability only drops by 3–4% using our aFACS system. The developed aFACS system provides a benchtop solution for rapid, highly accurate single cell level sorting with high cell viability, in particular for sensitive cell types.