Department of Chemical Engineering, The Pennsylvania State University, University Park, State College, PA 16802.
Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, State College, PA 16802.
J Biomech Eng. 2020 Mar 1;142(3):0310051-9. doi: 10.1115/1.4046180.
Density and mechanical properties (e.g., compressibility or bulk modulus) are important cellular biophysical markers. As such, developing a method to separate cells directly based on these properties can benefit various applications including biological research, diagnosis, prognosis, and therapeutics. As a potential solution, surface acoustic wave (SAW)-based cell separation has demonstrated advantages in terms of biocompatibility and compact device size. However, most SAW-reliant cell separations are achieved using an entangled effect of density, various mechanical properties, and size. In this work, we demonstrate SAW-based separation of cells/particles based on their density and compressibility, irrespective of their sizes, by manipulating the acoustic properties of the fluidic medium. Using our platform, SAW-based separation is achieved by varying the dimensions of the microfluidic channels, the wavelengths of acoustic signals, and the properties of the fluid media. Our method was applied to separate paraformaldehyde-treated and fresh Hela cells based on differences in mechanical properties; a recovery rate of 85% for fixed cells was achieved. It was also applied to separate red blood cells (RBCs) and white blood cells (WBCs) which have different densities. A recovery rate of 80.5% for WBCs was achieved.
密度和机械性能（例如，可压缩性或体积弹性模量）是重要的细胞生物物理标志物。因此，开发一种直接基于这些特性分离细胞的方法可以有益于各种应用，包括生物研究、诊断、预后和治疗。作为一种潜在的解决方案，基于表面声波（SAW）的细胞分离在生物相容性和设备紧凑尺寸方面具有优势。然而，大多数基于 SAW 的细胞分离都是通过密度、各种机械性能和大小的纠缠效应来实现的。在这项工作中，我们通过操纵流体制动的声学特性，证明了基于密度和可压缩性的 SAW 细胞/颗粒分离，而与它们的大小无关。使用我们的平台，通过改变微流道的尺寸、声信号的波长和流体介质的性质来实现基于 SAW 的分离。我们的方法应用于基于机械性能差异分离多聚甲醛处理和新鲜的 Hela 细胞，固定细胞的回收率达到 85%。它还应用于分离密度不同的红细胞（RBC）和白细胞（WBC），WBC 的回收率达到 80.5%。
