Department of Electrical Engineering and Computer Science, The University of Tennessee, Knoxville, TN, 37996, USA.
Department of Public Health, The University of Tennessee, Knoxville, TN, 37996, USA.
Mikrochim Acta. 2024 Oct 30;191(11):718. doi: 10.1007/s00604-024-06798-z.
Lead ion (Pb) pollution is a critical global issue due to its ability to accumulate in the human body, resulting in severe health problems. Despite extensive research efforts devoted to the detection of Pb contamination, practical, rapid, and field-deployable sensors for Pb is yet to be developed to effectively safeguard the environment and public health. Herein, a label-free affinity-based sensing device is developed based on printed circuit board (PCB) for low-cost, easy-to-use, and real-time on-site detection of Pb ions. The sensors are prepared by forming a self-assembled monolayer of glutathione (GSH) on the surface of gold-plated PCB electrodes, which serves as a molecular probe to recognize Pb. Rapid and sensitive detection is achieved by using capacitance sensing integrated with microfluidic enrichment. The sensor's interfacial capacitance is used to indicate specific binding, while the capacitance reading process simultaneously induces alternating current electrothermal (ACET) acceleration of analyte's travel towards the probes. Thus, the enrichment and detection are integrated into a single step, making pre-concentration unnecessary and shortening the assay time to 30 s. This Pb sensor has demonstrated one of the lowest limits of detection reported so far (1.85 fM) with a linear range of 0.01-10 pM. To evaluate the sensor's specificity, non-target metal ions are tested, all showing negligible responses. Testing of tap water sample also yields reasonable results, validating the sensor's robustness. The above-mentioned features, together with a commercial portable readout, make this sensor well-suited for point-of-use Pb detection at low cost.
铅离子（Pb）污染是一个全球性的重大问题，因为它能够在人体内积累，导致严重的健康问题。尽管已经投入了大量的研究努力来检测 Pb 污染，但仍需要开发实用、快速且可现场部署的 Pb 传感器，以有效保护环境和公众健康。在此，我们基于印刷电路板（PCB）开发了一种无标记的基于亲和力的传感设备，用于低成本、易于使用和实时现场检测 Pb 离子。传感器通过在镀金 PCB 电极表面形成谷胱甘肽（GSH）的自组装单分子层来制备，作为识别 Pb 的分子探针。通过电容传感与微流控富集相结合，实现快速和灵敏的检测。传感器的界面电容用于指示特异性结合，而电容读取过程同时诱导分析物向探针的交流电热（ACET）加速。因此，富集和检测集成到一个步骤中，无需预浓缩，将分析时间缩短至 30 秒。该 Pb 传感器具有迄今为止报道的最低检测限之一（1.85 fM），线性范围为 0.01-10 pM。为了评估传感器的特异性，测试了非目标金属离子，它们的响应都可以忽略不计。对自来水样品的测试也得到了合理的结果，验证了传感器的稳健性。上述特点，加上商用便携式读取器，使得这种传感器非常适合低成本的现场使用 Pb 检测。
