1 Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore, India.
SLAS Technol. 2017 Feb;22(1):73-80. doi: 10.1177/2211068216663604. Epub 2016 Sep 26.
Portable microfluidic diagnostic devices, including flow cytometers, are being developed for point-of-care settings, especially in conjunction with inexpensive imaging devices such as mobile phone cameras. However, two pervasive drawbacks of these have been the lack of automated sample preparation processes and cells settling out of sample suspensions, leading to inaccurate results. We report an automated blood sample preparation unit (ABSPU) to prevent blood samples from settling in a reservoir during loading of samples in flow cytometers. This apparatus automates the preanalytical steps of dilution and staining of blood cells prior to microfluidic loading. It employs an assembly with a miniature vibration motor to drive turbulence in a sample reservoir. To validate performance of this system, we present experimental evidence demonstrating prevention of blood cell settling, cell integrity, and staining of cells prior to flow cytometric analysis. This setup is further integrated with a microfluidic imaging flow cytometer to investigate cell count variability. With no need for prior sample preparation, a drop of whole blood can be directly introduced to the setup without premixing with buffers manually. Our results show that integration of this assembly with microfluidic analysis provides a competent automation tool for low-cost point-of-care blood-based diagnostics.
便携式微流控诊断设备，包括流式细胞仪，正在为即时检测环境开发，特别是与廉价的成像设备（如手机摄像头）结合使用时。然而，这些设备存在两个普遍的缺点，即缺乏自动化的样本制备过程和细胞从样本悬浮液中沉淀，导致结果不准确。我们报告了一种自动血液样本制备单元（ABSPU），以防止在将样本加载到流式细胞仪时样本储液器中的血液样本沉淀。该设备可自动对微流加载前的血细胞进行稀释和染色的预分析步骤。它采用了一个带有微型振动电机的组件，以在样本储液器中产生湍流。为了验证该系统的性能，我们提供了实验证据，证明了该系统可以防止血细胞沉淀、细胞完整性和在流式细胞分析前对细胞进行染色。该装置进一步与微流成像流式细胞仪集成，以研究细胞计数的可变性。由于无需事先进行样品制备，只需将一滴全血直接引入该装置，而无需手动与缓冲液预混合。我们的结果表明，将该组件与微流分析集成提供了一种用于低成本即时护理基于血液诊断的有竞争力的自动化工具。
