Olofsson Karl, Hammarström Björn, Wiklund Martin
Department of Applied Physics, KTH Royal Institute of Technology, Sweden.
Lab Chip. 2020 Jun 7;20(11):1981-1990. doi: 10.1039/d0lc00175a. Epub 2020 May 1.
The acoustic radiation force, originating from ultrasonic standing waves and utilized in numerous cell oriented acoustofluidic applications, is dependent on the acoustic contrast factor which describes the relationship between the acousto-mechanical properties of a particle and its surrounding medium. The acousto-mechanical properties of a cell population are known to be heterogeneously distributed but are often assumed to be constant over time. In this paper, we use microchannel acoustophoresis to show that the cell state within a cell population, in our case living and dead cells, influences the mechanical phenotype. By investigating the trapping location of viable and dead K562, MCF-7 and A498 cells as a function of the suspension medium density, we observed that beyond a specific medium density the viable cells were driven to the pressure anti-node while the dead cells were retained in the pressure node. Using this information, we were able to calculate the effective acoustic impedance of viable K562 and MCF-7 cells. The spatial separation between viable and dead cells along the channel width demonstrates a novel acoustophoresis approach for binary separation of viable and dead cells in a cell-size independent and robust manner.
声辐射力源于超声驻波，在众多面向细胞的声流控应用中得到应用，它取决于声对比度因子，该因子描述了粒子的声机械特性与其周围介质之间的关系。已知细胞群体的声机械特性呈异质分布，但通常假定其随时间保持恒定。在本文中，我们使用微通道声泳来表明细胞群体中的细胞状态，在我们的案例中即活细胞和死细胞，会影响机械表型。通过研究活的和死的K562、MCF - 7和A498细胞的捕获位置作为悬浮介质密度的函数，我们观察到超过特定介质密度时，活细胞被驱动到压力波腹，而死细胞则保留在压力波节处。利用这些信息，我们能够计算活的K562和MCF - 7细胞的有效声阻抗。活细胞和死细胞沿通道宽度的空间分离展示了一种新颖的声泳方法，可用于以与细胞大小无关且稳健的方式对活细胞和死细胞进行二元分离。
