Liu Ruxiu, Wang Ningquan, Kamili Farhan, Sarioglu A Fatih
School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Lab Chip. 2016 Apr 21;16(8):1350-7. doi: 10.1039/c6lc00209a.
Numerous biophysical and biochemical assays rely on spatial manipulation of particles/cells as they are processed on lab-on-a-chip devices. Analysis of spatially distributed particles on these devices typically requires microscopy negating the cost and size advantages of microfluidic assays. In this paper, we introduce a scalable electronic sensor technology, called microfluidic CODES, that utilizes resistive pulse sensing to orthogonally detect particles in multiple microfluidic channels from a single electrical output. Combining the techniques from telecommunications and microfluidics, we route three coplanar electrodes on a glass substrate to create multiple Coulter counters producing distinct orthogonal digital codes when they detect particles. We specifically design a digital code set using the mathematical principles of Code Division Multiple Access (CDMA) telecommunication networks and can decode signals from different microfluidic channels with >90% accuracy through computation even if these signals overlap. As a proof of principle, we use this technology to detect human ovarian cancer cells in four different microfluidic channels fabricated using soft lithography. Microfluidic CODES offers a simple, all-electronic interface that is well suited to create integrated, low-cost lab-on-a-chip devices for cell- or particle-based assays in resource-limited settings.
许多生物物理和生化分析依赖于在芯片实验室设备上处理颗粒/细胞时对其进行空间操控。分析这些设备上空间分布的颗粒通常需要显微镜检查，这抵消了微流控分析在成本和尺寸方面的优势。在本文中，我们介绍了一种可扩展的电子传感器技术，称为微流控编码（microfluidic CODES），它利用电阻脉冲传感从单个电输出正交检测多个微流控通道中的颗粒。结合电信和微流控技术，我们在玻璃基板上布置三个共面电极，以创建多个库尔特计数器，当它们检测到颗粒时会产生不同的正交数字代码。我们使用码分多址（CDMA）电信网络的数学原理专门设计了一个数字代码集，即使这些信号重叠，也能通过计算以超过90%的准确率解码来自不同微流控通道的信号。作为原理验证，我们使用该技术在通过软光刻制造的四个不同微流控通道中检测人卵巢癌细胞。微流控编码提供了一个简单的全电子接口，非常适合在资源有限的环境中创建用于基于细胞或颗粒分析的集成、低成本芯片实验室设备。
