An update on polydiacetylene-based solid-supported sensing platforms for environmental and health monitoring

Polydiacetylenes (PDAs) are a unique class of conjugated polymers renowned for their pronounced chromo- and fluorogenic responses to external stimuli, enabling direct optical transduction of chemical and biological interactions. While early PDA-based sensing systems predominantly relied on solution-phase assemblies, their limited structural stability, reproducibility, and deployability have constrained practical applications. In recent years, the immobilization of PDAs onto solid supports has emerged as a powerful strategy to overcome these limitations, transforming responsive supramolecular polymers into robust, functional sensing platforms. Solid-supported PDA architectures offer enhanced mechanical stability, improved environmental tolerance, controlled molecular organization, and compatibility with portable and field-deployable devices. This review provides a comprehensive and application-oriented overview of solid-supported polydiacetylene systems for environmental and health monitoring. Emphasis is placed on the role of support materials, fabrication strategies, and structure-process-property relationships that govern sensing performance. Key applications in environmental pollutant detection and biomedical diagnostics are critically examined, alongside comparative performance metrics and design considerations. Current challenges, including signal irreversibility, environmental interference, and scalability, are discussed, and future directions toward sustainable fabrication, wearable devices, and integrated smart sensing platforms are outlined. By positioning solid-supported PDAs as adaptive interfaces between molecular recognition and macroscopic readout, this review highlights their potential as next-generation materials for decentralized and real-world sensing applications.