Adsorption of a biofouling layer on the surface of biosensors decreases the electrochemical activity and hence shortens the service life of biosensors, particularly implantable and wearable biosensors. Real-time quantification of the loss of activity is important for in situ assessment of performance while presenting an opportunity to compensate for the loss of activity and recalibrate the sensor to extend the service life. Here, we introduce an electrochemical noise measurement technique as a tool for the quantification of the formation of a biofouling layer on the surface of gold. The technique uniquely affords thermodynamic and kinetic information without applying an external bias (potential and/or current), hence allowing the system to be appraised in its innate state. The technique relies on the analysis of non-faradaic current and potential fluctuations that are intrinsically generated by the interaction of charged species at the electrode surface, i.e., gold. An analytical model is extended to explain the significance of parameters drawn from statistical analysis of the noise signal. This concept is then examined in buffered media in the presence of albumin, a common protein in the blood and a known source of a fouling layer in biological systems. Results indicate that the statistical analysis of the noise signal can quantify the loss of electrochemical activity, which is also corroborated by impedance spectroscopy as a complementary technique.

中文翻译：

---

金上生物污垢层的随机电化学测量


生物传感器表面生物污垢层的吸附会降低电化学活性，从而缩短生物传感器的使用寿命，特别是可植入和可穿戴生物传感器。活性损失的实时量化对于性能的原位评估非常重要，同时提供了补偿活性损失和重新校准传感器以延长使用寿命的机会。在这里，我们介绍一种电化学噪声测量技术，作为量化金表面生物污垢层形成的工具。该技术独特地提供热力学和动力学信息，无需施加外部偏置（电势和/或电流），因此允许系统在其固有状态下进行评估。该技术依赖于对非法拉第电流和电位波动的分析，这些波动本质上是由电极表面（即金）的带电物质相互作用产生的。分析模型被扩展以解释从噪声信号的统计分析中得出的参数的重要性。然后在存在白蛋白的缓冲介质中检查这个概念，白蛋白是血液中的常见蛋白质，也是生物系统中已知的污垢层来源。结果表明，噪声信号的统计分析可以量化电化学活性的损失，这也得到了阻抗谱作为补充技术的证实。