德克萨斯大学：研究石墨烯电子纹身电生理传感，用于潜水员安全检测

危险且缺乏保护的水下作业是潜水员死亡的主要原因；生物传感器可提供早期预警和部分保护，从而在一定程度上减轻这一风险。然而，当前生物传感器的复杂性和高成本限制了其广泛应用，凸显了对有效、成本效益高且多功能生理监测解决方案的迫切需求。本文，德克萨斯大学Deji Akinwande、马萨诸塞大学Dmitry Kireev等在《ACS Applied Electronic Materials》期刊发表名为“Electrophysiological Sensing with Graphene Electronic Tattoos for Saline and Underwater Environments”的论文，研究开发了一种非侵入式防水石墨烯电生理传感器，可在盐水环境中检测多种生理信号，从而克服现有水下监测技术的局限性。通过采用原子级薄的石墨烯界面和简单的防水涂层方法，我们实现了在皮肤表面采集心电图（ECG）、肌电图（EMG）和皮肤电活动（EDA）信号。

此外，我们通过EDA信号准确评估了惊吓事件，这对于评估潜水员压力和预防事故至关重要。该防水石墨烯生物传感器展现出卓越的电学性能，包括在10 kHz频率下阻抗低至约2.4 kΩ·cm²、EMG信号信噪比超过21 dB，以及EDA信号响应速度高达0.125 μS/(s·cm²)，所有测试均在盐水条件下进行。本研究为防水石墨烯电生理传感器在盐水环境中的巨大潜力提供了有力证据，为提升潜水员安全性和降低事故风险提供了解决方案。

2图文导读

图1. Water-resistant GET (Graphene Electronic Tattoo) structure and functional diagram. (a) Schematic representation of the integrated structure of SCC-GET. (b) Close-up optical photograph of a single GET, and a GET connected to gold tape adhered to the forearm. The skin surface has been treated with a waterproof coating. (c) Schematic representation of a SCC-GET sensor, which is capable of detecting electrocardiogram (ECG), electromyogram (EMG), and electrodermal activity (EDA) signals in saline environments.

图2. Comparative impedance spectra of GET under diverse coating conditions for water resistance performance. (a) Skin crack care (SCC) coated GET full spectrum impedance sweep for all test conditions. (b) The mean impedance of GET using different waterproofing methods (Tegaderm film-coated commercial electrodes, Tegaderm film-coated GET, Skin Crack Care (SCC) coated GET, and Waterproof spray-coated GET), under different test conditions (bare in air, coated in air, coated in DI water, and coated in PBS solution), measured at different frequencies (100 Hz, 1 kHz, and 10 kHz). The area of the commercial electrodes was normalized to match the surface area of the GET for comparative analysis.

图3. ECG signal recorded from SCC coated GET. (a) ECG signals measured in air from GET (light orange), under 30 cm of deionized (DI) water (light blue), under 30 cm of PBS solution (dark blue), and Ag/AgCl commercial electrodes (green) in air. (b) ECG signal measured by GET in air, capturing a complete cardiac cycle and marking the different phases within the cycle. (c) Violin plot of sinus rhythm R–R intervals (heart rate) calculated from ECG signals under different conditions. The width of the violin represents the data density, the center bar shows the interquartile range, and the dot within the bar marks the median. (d) Diagram of three-lead ECG signal measurement.

图4. EMG signal recorded from SCC coated GET. (a) EMG signals measured simultaneously in air from SCC-GET (dark orange) and Ag/AgCl commercial electrodes (green). EMG signals from SCC-GET measured under 30 cm of deionized (DI) water (light blue) and under 30 cm of PBS solution (dark blue). (b) Signal-to-noise ratio for different measurement conditions (n= 12, 10 grabs, and 2 holds). The bars represent the mean values, with error bars indicating the standard deviation (mean ± SD). (c) Optical photograph of simultaneous EMG signal measurements using graphene electrodes and commercial electrodes (cut into 0.25 cm2), located on the subject’s forearm.

图5. EDA signal recorded from SCC coated GET. (a) Schematic diagram of the working principle for EDA signal measurement. (b) EDA signals measured with SCC-GET in DI water, recorded while subjects watched three types of videos: meditative, serene, and terrifying. The green dashed line indicates where subjects stabilized their emotional fluctuations, while the green arrow highlights the specific moment. (c) EDA signals measured with SCC-GET in DI water, recorded while subjects watched a 10 min terrifying video. (d) Comparison of EDA signal peaks (using area-normalized conductance) while watching terrifying videos measured with SCC-GET under different conditions (DI water, PBS, air) and commercial electrodes (air only). Normalized by area (n= 9 for commercial metal button electrodes in air,n= 9 for bare GET in air,n= 7 for SCC-GET in air,n= 6 for SCC-GET in DI,n= 8 for SCC-GET in PBS). The box represents 25% and 75% with a mean; outliers are ±SD. (e) Comparison of EDA signals baselines (median of tonic component), using area-normalized conductance, measured with GET under different conditions and commercial electrodes in air.

3小结

研究推出了一种新型皮肤裂纹护理增强型防水石墨烯电子纹身（SCC-GET），展示了其在盐水环境中各种生物电子应用中的有效性。通过将原子级薄的石墨烯与柔性、透明且防水的层相结合，SCC-GET实现了亚微米级厚度，并能与人体皮肤无缝贴合，不受运动影响，使其成为迄今为止在盐水条件下报道的最薄的电生理传感器。SCC-GET的便捷组装特性使其可同时放置于多个身体部位以同步检测生命体征信号。总体而言，本研究证实了SCC-GET在多种生物电子应用中的优异性能与可靠性，为先进生理监测系统的发展奠定了基础，尤其在海洋等极端环境中具有广阔应用前景。

审核编辑 黄宇