Polydiacetylene-Based Colorimetric and Fluorescent Chemosensor for the Detection of Carbon Dioxide

We developed a colorimetric and fluorescent turn-on carbon dioxide sensor that relies on a polydiacetylene, <b>PDA-1</b>, functionalized with amines and imidazolium groups. The pendant amines react with CO₂ under basic conditions to form carbamoate anions, which partially neutralize the polymer’s positive charges, inducing a phase transition. <b>PDA-1</b> allows for the selective sensing of CO₂ with high sensitivity, down to atmospheric concentrations. Naked-eye detection of CO₂ is accomplished either in water solutions of <b>PDA-1</b> or in the solid state with electrospun coatings of <b>PDA-1</b> nanofibers