Colorimetric transition pathway mapping in polydiacetylene by hyperspectral microscopy

The structural variance of polydiacetylene (PDA) at the nanoscale even under the same fabrication conditions is one of the origins of its poor reproducibility in chemo/biosensing. In this work, we present a spatial map of such structural distributions within a single crystal by taking an advantage of the recent development of hyperspectral microscopy in visible wavelength. Hyperspectral microscopy provides the distribution of absorption spectra at the spatial resolution of the standard optical microscopy. By track-ing the blue-to-red transition via this technique, we found that the heat application leaves a fingerprint in the transition pathways.