Recent advances in solid-contact ion-selective electrodes: functional materials, transduction mechanisms, and development trends

From environmental monitoring to point-of-care biofluid analysis, rapid ion determination requires robust analytical tools. In recent years, driven by the development of materials science and processing technology, solid-contact ion-selective electrodes (SC-ISEs) with high-performance functional materials and creative structures have shown great potential for routine and portable ion detection. In particular, the introduction of nanomaterials as ion-to-electron transducers and the adoption of different performance enhancement strategies have significantly promoted the development of SC-ISEs. Besides, with the increasing miniaturization, flexibility, and dependability of SC-ISEs, this field has gradually begun to evolve from conventional potentiometric ion sensing to integrated sensing systems with broader application scenarios. This comprehensive review covers pioneering research on functional materials and state-of-the-art technologies for the construction of SC-ISEs, with an emphasis on new development trends and applications.