In various embodiments, the present invention is directed to a supraparticle for use in producing structural colors comprising a plurality of core/shell nanoparticles having a melanin or synthetic melanin core and a silica shell having a plurality of silanol groups on its outer surface and a poly(ethylene glycol) (PEG) crosslinker. In various embodiments, the structure of these crosslinked supra particles is reinforced by hydrogen bonds formed between the silanol groups on the core-shell nanoparticles and mechanical, solution phase, and dry state stability.