Polydiacetylene Supramolecules: Synthesis, Characterization, and Emerging Applications

Polydiacetylenes are a class of polymers with unique optical properties. Upon photopolymerization, monomers form a deep blue, nonfluorescent polymer, which transitions to a red, fluorescent polymer in response to various environmental factors such as pH, temperature, or molecular binding. The chromatic and emissive properties of polydiacetylenes have generated considerable popularity for their use in biosensing applications over the past three decades. The versatility of polydiacetylene forms has also allowed for a wide range of sensors including liposome bacterial sensors, films for detecting influenza virus, hydrogels for protein detection, and printed ink for the detection of volatile organic compounds. In this article, we review the wide range of techniques employed in the development of polydiacetylene sensors and summarize methods to modify, characterize, and analyze polydiacetylene-based sensing systems. Additionally, we discuss the recent directions of polydiacetylene materials outside of sensing applications as versatile tools in biomedicine and tissue engineering.