Surface functionalization strategies for polydiacetylene-based colorimetric sensors

Polydiacetylene (PDA)-based colorimetric sensors offer a promising platform for rapid and visual detection, through a chromatic transition from blue to red. However, their broader applications are hindered by challenges in sensitivity, selectivity, and stability. This review comprehensively overviews functionalization strategies to overcome existing limitations, including chemical modification with reactive groups, conjugation with specific ligands or receptors, and integration with nanomaterials. Alternative approaches are also discussed. The interplay between base materials, deposition methods, and functionalization efficiencies is emphasized. Furthermore, this review addresses remaining challenges, proposes feasible solutions, and offers insights into future strategic directions for creating more advanced PDA-based colorimetric sensors.