Fig. 3
From: Multifunctional fish gelatin hydrogel inverse opal films for wound healing
The pH responsiveness of the IOF fabricated by replicating CCA templates with a nanoparticle size of 220Â nm. a Optical images and variation of the reflection peaks during pH value increasing from 4.0 to 8.0. b The changes of reflection peak wavelength upon pH increase. c The switch value of the reflection peak of the IOF in the pH 5 and 8 buffers as a function of the pH cycle numbers