Biomicrofluidics. 2012 Jun;6(2):24114-2411413. doi: 10.1063/1.4705368. Epub 2012 Apr 20.
Miniaturization in biological analyses has several advantages, such as sample volume reduction and fast response time. The integration of miniaturized biosensors within lab-on-a-chip setups under flow conditions is highly desirable, not only because it simplifies process handling but also because measurements become more robust and operator-independent. In this work, we study the integration of flow amperometric biosensors within a microfluidic platform when analyte concentration is indirectly measured. As a case study, we used a platinum miniaturized glucose biosensor, where glucose is enzymatically converted to [Formula: see text] that is oxidized at the electrode. The experimental results produced are strongly coupled to a theoretical analysis of fluid dynamic conditions affecting the electrochemical response of the sensor. We verified that the choice of the inlet flow rate is a critical parameter in flow biosensors, because it affects both glucose and [Formula: see text] transport, to and from the electrode. We identify optimal flow rate conditions for accurate sensing at high time resolution. A dimensionless theoretical analysis allows the extension of the results to other sensing systems according to fluid dynamic similarity principles. Furthermore, we developed a microfluidic design that connects a sampling unit to the biosensor, in order to decouple the sampling flow rate from that of the actual measurement.
在生物分析中，微型化具有几个优点，例如减少样品量和缩短响应时间。在流动条件下，将微型化生物传感器集成到芯片实验室设置中是非常理想的，这不仅因为它简化了处理过程，而且还因为测量变得更加稳健和不受操作人员影响。在这项工作中，我们研究了在间接测量分析物浓度时，将流动安培生物传感器集成到微流控平台中的情况。作为一个案例研究，我们使用了一种铂微型化葡萄糖生物传感器，其中葡萄糖在酶的作用下转化为[Formula: see text]，然后在电极上被氧化。实验结果与影响传感器电化学响应的流体动力学条件的理论分析密切相关。我们验证了入口流速的选择是流动生物传感器中的一个关键参数，因为它会影响葡萄糖和[Formula: see text]向电极的传输。我们确定了在高时间分辨率下进行准确感应的最佳流速条件。无因次理论分析允许根据流体动力学相似性原理将结果扩展到其他传感系统。此外，我们开发了一种微流控设计，将采样单元连接到生物传感器，以将采样流速与实际测量流速解耦。
