Abstract: Disclosed is a thermoreversible synthesis of a new type of material made by embedding a colloidal population within a thermo-reversibly gelled polymer. The polymer may be a physically cross-linked PVA hydrogel. PVA hydrogels are non-toxic, biocompatible, mechanically robust, and elastic. The present invention TGCCA diffraction is similar to that of photo-polymerized PCCA. The present invention TGCCA can be irreversibly covalently cross-linked using glutaraldehyde. The cross-linked TGCCA can be made responsive to chemical stimuli by functionalizing the hydrogel hydroxyl groups. The diffraction of carboxyl or amine functionalized TGCCA was monitored as a function of the pH and determined diffraction wavelengths titrate with the pKa of the functional group. It was also demonstrated that TGCCA could be fabricated in arbitrarily large volumes and shapes. The present invention method fabricates inexpensive homogenously diffracting chemically modifiable TGCCA.