Department of Mechanical and Industrial Engineering, University of Massachusetts Amherst, Amherst, MA, USA.
Institute for Applied Life Sciences, University of Massachusetts Amherst, Amherst, MA, USA.
Nat Commun. 2021 Mar 19;12(1):1755. doi: 10.1038/s41467-021-21974-y.
All-electronic interrogation of biofluid flow velocity by electrical nanosensors incorporated in ultra-low-power or self-sustained systems offers the promise of enabling multifarious emerging research and applications. However, existing nano-based electrical flow sensing technologies remain lacking in precision and stability and are typically only applicable to simple aqueous solutions or liquid/gas dual-phase mixtures, making them unsuitable for monitoring low-flow (~micrometer/second) yet important characteristics of continuous biofluids (such as hemorheological behaviors in microcirculation). Here, we show that monolayer-graphene single microelectrodes harvesting charge from continuous aqueous flow provide an effective flow sensing strategy that delivers key performance metrics orders of magnitude higher than other electrical approaches. In particular, over six-months stability and sub-micrometer/second resolution in real-time quantification of whole-blood flows with multiscale amplitude-temporal characteristics are obtained in a microfluidic chip.
通过整合在超低功率或自维持系统中的电纳米传感器对生物流体流速进行全电子检测，有望实现各种新兴研究和应用。然而，现有的基于纳米的电流量感技术在精度和稳定性方面仍然存在不足，通常仅适用于简单的水溶液或液/气双相混合物，因此不适合监测低流速（~微米/秒）但对连续生物流体很重要的特性（例如微循环中的血液流变特性）。在这里，我们表明，从连续水流中采集电荷的单层石墨烯单微电子电极提供了一种有效的流量检测策略，其关键性能指标比其他电方法高出几个数量级。特别是，在微流控芯片中获得了具有多尺度幅度-时间特征的全血流动的六个月以上稳定性和亚微米/秒分辨率的实时定量。
