Micro- and Nanosystems (MNS), Department of Electrical Engineering (ESAT), KU Leuven, Leuven, Belgium.
Chemical and Biochemical Reactor Engineering and Safety (CREaS), Department of Chemical Engineering, KU Leuven, Leuven, Belgium.
Lab Chip. 2023 Sep 26;23(19):4276-4286. doi: 10.1039/d3lc00645j.
Current single-cell technologies require large and expensive equipment, limiting their use to specialized labs. In this paper, we present for the first time a microfluidic device which demonstrates a combined method for full-electric cell capturing, analyzing, and selectively releasing with single-cell resolution. All functionalities are experimentally demonstrated on . Our microfluidic platform consists of traps centered around a pair of individually accessible coplanar electrodes, positioned under a microfluidic channel. Using this device, we validate our novel Two-Voltage method for trapping single cells by positive dielectrophoresis (pDEP). Cells are attracted to the trap when a high voltage (VH) is applied. A low voltage (VL) holds the already trapped cell in place without attracting additional cells, allowing full control over the number of trapped cells. After trapping, the cells are analyzed by broadband electrochemical impedance spectroscopy. These measurements allow the detection of single cells and the extraction of cell parameters. Additionally, these measurements show a strong correlation between average phase change and cell size, enabling the use of our system for size measurements in biological applications. Finally, our device allows selectively releasing trapped cells by turning off the pDEP signal in their trap. The experimental results show the techniques potential as a full-electric single-cell analysis tool with potential for miniaturization and automation which opens new avenues towards small-scale, high throughput single-cell analysis and sorting lab-on-CMOS devices.
目前的单细胞技术需要大型和昂贵的设备，这限制了它们在专门实验室中的使用。在本文中，我们首次展示了一种微流控设备，该设备展示了一种结合方法，可实现全电动细胞捕获、分析和以单细胞分辨率进行选择性释放。所有功能都在. 上进行了实验验证。我们的微流控平台由围绕一对可单独访问的共面电极的阱组成，这些电极位于微流道下方。使用该设备，我们通过正介电泳（pDEP）验证了我们用于捕获单细胞的新型双电压方法。当施加高电压 (VH) 时，细胞会被吸引到阱中。低电压 (VL) 将已经捕获的细胞固定在适当位置，而不会吸引额外的细胞，从而可以完全控制捕获的细胞数量。捕获后，通过宽带电化学阻抗谱对细胞进行分析。这些测量允许检测单个细胞并提取细胞参数。此外，这些测量显示平均相位变化与细胞大小之间存在很强的相关性，这使得我们的系统可用于生物应用中的尺寸测量。最后，我们的设备可以通过关闭细胞阱中的 pDEP 信号来选择性地释放捕获的细胞。实验结果表明，该技术具有作为全电动单细胞分析工具的潜力，具有小型化和自动化的潜力，为小型化、高通量单细胞分析和排序的 CMOS 设备开辟了新途径。
