Swelling-Induced Chromotropism of Bionanocomposite Hydrogel Beads

Langmuir. 2024 Jan 9;40(1):1016-1023. doi: 10.1021/acs.langmuir.3c03232. Epub 2023 Dec 6.

Abstract

Monodispersed gelatin hydrogel beads containing smectite with adsorbed cyanine dye exhibit chromotropic responses to compression and swelling/deswelling by solvent. Photoluminescence color of the beads changes by swelling in water (blue) and deswelling in ethanol (purple) reversibly. The forces generated by swelling/deswelling are thought to induce the transition between the J-aggregate and the monomer of cyanine dye adsorbed on smectite, giving the photoluminescent color changes.