Yeasmin Sanjida, Cheng Li-Jing
School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331, USA.
Biomicrofluidics. 2024 May 17;18(3):031503. doi: 10.1063/5.0194200. eCollection 2024 May.
Molecularly imprinted polymers (MIPs), functioning as artificial bioreceptors, hold significant promise for biomarker detection in healthcare, disease diagnosis, and addressing drug abuse. In contrast to natural bioreceptors, MIP-based sensors offer numerous advantages, such as high stability, cost-effectiveness, high selectivity, sensitivity, and notably straightforward preparation with customizable binding sites for diverse targets. Conventional MIP sensors often necessitate external redox reagents in analytes to transduce binding events into electrochemical signals for indirect detection, presenting challenges for practical applications in wearables or point-of-care (POC) testing. Redox-active MIP sensors have emerged as a viable alternative, enabling direct and label-free electrochemical detection, with two types developed. The first type utilizes electrocatalytic materials to expedite electron transfer and facilitate a redox reaction between the captured electroactive target and the electrode. The second type incorporates an embedded redox reactive component that allows selective binding of a target to modulate its electron transfer, leading to a change in the electrical signal. This review covers emerging trends and challenges in redox-active MIP sensors for direct electrochemical detection of biomarkers, focusing on sensing mechanisms, synthesis methods, and applications. Additionally, recent progress in wearable and POC redox-active MIP sensors is highlighted. A comprehensive outlook of challenges is further provided, aiming to advance direct biomarker detection for diverse healthcare applications.
分子印迹聚合物（MIPs）作为人工生物受体，在医疗保健、疾病诊断以及解决药物滥用问题中的生物标志物检测方面具有巨大潜力。与天然生物受体相比，基于MIP的传感器具有诸多优势，如高稳定性、成本效益高、高选择性、灵敏度高，并且制备过程特别简单，可为不同目标定制结合位点。传统的MIP传感器通常需要在分析物中使用外部氧化还原试剂，将结合事件转化为电化学信号以进行间接检测，这给可穿戴设备或即时检测（POC）中的实际应用带来了挑战。氧化还原活性MIP传感器已成为一种可行的替代方案，能够实现直接的无标记电化学检测，目前已开发出两种类型。第一种类型利用电催化材料加速电子转移，并促进捕获的电活性目标与电极之间的氧化还原反应。第二种类型包含一个嵌入式氧化还原反应成分，该成分允许目标选择性结合以调节其电子转移，从而导致电信号发生变化。本综述涵盖了用于生物标志物直接电化学检测的氧化还原活性MIP传感器的新兴趋势和挑战，重点关注传感机制、合成方法及应用。此外，还强调了可穿戴和POC氧化还原活性MIP传感器的最新进展。进一步提供了对挑战的全面展望，旨在推动用于各种医疗应用的生物标志物直接检测。
