Chem Rev. 2019 Apr 24;119(8):5248-5297. doi: 10.1021/acs.chemrev.8b00655. Epub 2019 Mar 22.
pH-sensing materials and configurations are rapidly evolving toward exciting new applications, especially those in biomedical applications. In this review, we highlight rapid progress in electrochemical pH sensors over the past decade (2008-2018) with an emphasis on key considerations, such as materials selection, system configurations, and testing protocols. In addition to recent progress in optical pH sensors, our main focus in this review is on electromechanical pH sensors due to their significant advances, especially in biomedical applications. We summarize developments of electrochemical pH sensors that by virtue of their optimized material chemistries (from metal oxides to polymers) and geometrical features (from thin films to quantum dots) enable their adoption in biomedical applications. We further present an overview of necessary sensing standards and protocols. Standards ensure the establishment of consistent protocols, facilitating collective understanding of results and building on the current state. Furthermore, they enable objective benchmarking of various pH-sensing reports, materials, and systems, which is critical for the overall progression and development of the field. Additionally, we list critical issues in recent literary reporting and suggest various methods for objective benchmarking. pH regulation in the human body and state-of-the-art pH sensors (from ex vivo to in vivo) are compared for suitability in biomedical applications. We conclude our review by (i) identifying challenges that need to be overcome in electrochemical pH sensing and (ii) providing an outlook on future research along with insights, in which the integration of various pH sensors with advanced electronics can provide a new platform for the development of novel technologies for disease diagnostics and prevention.
pH 感测材料和配置正在迅速发展，出现了许多令人兴奋的新应用，特别是在生物医学应用方面。在这篇综述中，我们重点介绍了过去十年（2008-2018 年）电化学 pH 传感器的快速发展，强调了关键考虑因素，如材料选择、系统配置和测试协议。除了最近光学 pH 传感器的进展外，我们主要关注的是机电 pH 传感器，因为它们在生物医学应用方面取得了显著进展。我们总结了电化学 pH 传感器的发展情况，这些传感器得益于其优化的材料化学（从金属氧化物到聚合物）和几何特征（从薄膜到量子点），使其能够应用于生物医学领域。我们进一步介绍了必要的感测标准和协议。标准确保了一致协议的建立，有助于对结果的集体理解，并建立在当前状态的基础上。此外，它们还可以对各种 pH 感测报告、材料和系统进行客观的基准测试，这对于该领域的整体进展和发展至关重要。此外，我们列出了最近文献报道中的关键问题，并提出了各种客观基准测试的方法。我们比较了人体的 pH 调节和最先进的 pH 传感器（从离体到体内），以确定它们在生物医学应用中的适用性。最后，我们通过（i）确定电化学 pH 感测中需要克服的挑战，以及（ii）提供未来研究的展望和见解来结束综述，其中各种 pH 传感器与先进电子设备的集成可以为疾病诊断和预防新技术的发展提供一个新平台。
