Department of Biomedical Engineering (BME), National University of Singapore, Singapore, Singapore.
Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
Nat Mater. 2024 Aug;23(8):1115-1122. doi: 10.1038/s41563-024-01918-9. Epub 2024 Jun 12.
Continuous and in situ detection of biomarkers in biofluids (for example, sweat) can provide critical health data but is limited by biofluid accessibility. Here we report a sensor design that enables in situ detection of solid-state biomarkers ubiquitously present on human skin. We deploy an ionic-electronic bilayer hydrogel to facilitate the sequential dissolution, diffusion and electrochemical reaction of solid-state analytes. We demonstrate continuous monitoring of water-soluble analytes (for example, solid lactate) and water-insoluble analytes (for example, solid cholesterol) with ultralow detection limits of 0.51 and 0.26 nmol cm, respectively. Additionally, the bilayer hydrogel electrochemical interface reduces motion artefacts by a factor of three compared with conventional liquid-sensing electrochemical interfaces. In a clinical study, solid-state epidermal biomarkers measured by our stretchable wearable sensors showed a high correlation with biomarkers in human blood and dynamically correlated with physiological activities. These results present routes to universal platforms for biomarker monitoring without the need for biofluid acquisition.
在生物流体（例如汗液）中进行连续的原位生物标志物检测可以提供关键的健康数据，但受到生物流体可及性的限制。在这里，我们报告了一种传感器设计，该设计可以在人体皮肤普遍存在的固态生物标志物的原位进行检测。我们采用离子-电子双层水凝胶来促进固态分析物的顺序溶解、扩散和电化学反应。我们证明了对水溶性分析物（例如固态乳酸盐）和水不溶性分析物（例如固态胆固醇）的连续监测，其超低检测限分别为 0.51 和 0.26 nmol cm。此外，与传统的液体感应电化学界面相比，双层水凝胶电化学界面将运动伪影降低了三倍。在一项临床研究中，我们的可拉伸可穿戴传感器测量的固态表皮生物标志物与人体血液中的生物标志物高度相关，并与生理活动动态相关。这些结果为无需采集生物流体即可进行生物标志物监测的通用平台提供了途径。
