Interconnected & Integrated Bioelectronics Lab (I²BL), Department of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, CA, USA.
Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, USA.
Nat Commun. 2020 Sep 2;11(1):4405. doi: 10.1038/s41467-020-18238-6.
Active biofluid management is central to the realization of wearable bioanalytical platforms that are poised to autonomously provide frequent, real-time, and accurate measures of biomarkers in epidermally-retrievable biofluids (e.g., sweat). Accordingly, here, a programmable epidermal microfluidic valving system is devised, which is capable of biofluid sampling, routing, and compartmentalization for biomarker analysis. At its core, the system is a network of individually-addressable microheater-controlled thermo-responsive hydrogel valves, augmented with a pressure regulation mechanism to accommodate pressure built-up, when interfacing sweat glands. The active biofluid control achieved by this system is harnessed to create unprecedented wearable bioanalytical capabilities at both the sensor level (decoupling the confounding influence of flow rate variability on sensor response) and the system level (facilitating context-based sensor selection/protection). Through integration with a wireless flexible printed circuit board and seamless bilateral communication with consumer electronics (e.g., smartwatch), contextually-relevant (scheduled/on-demand) on-body biomarker data acquisition/display was achieved.
主动生物流体管理是实现可穿戴生物分析平台的核心，这些平台有望自主提供表皮可提取生物流体（例如汗液）中生物标志物的频繁、实时和准确测量。因此，在这里设计了一种可编程的表皮微流控阀系统，该系统能够进行生物流体采样、路由和分隔以进行生物标志物分析。在其核心，该系统是一个由单独寻址的微加热控制热响应水凝胶阀组成的网络，增加了压力调节机制以适应与汗腺接口时的压力积聚。通过该系统实现的主动生物流体控制被用于在传感器层面（消除流速变化对传感器响应的干扰影响）和系统层面（促进基于上下文的传感器选择/保护）创造前所未有的可穿戴生物分析能力。通过与无线柔性印刷电路板集成并与消费电子产品（例如智能手表）进行无缝双边通信，实现了与上下文相关的（计划/按需）身体上生物标志物数据采集/显示。
