Clathrate Compounds with Quinone
Palin, D. E.; Powell, H. M. "Hydrogen Bond Linking of Quinol Molecules," Nature  156, 334 (1946), and DOI: 10.1039/DF9694800181

White aqueous starch/iod$ide$ tests for oxidizing agents by turning brown, liberated iodine and ionic oligomers intercalated within amylose starch (linear).  Amylopetcin (branched) gives red.  The mix is purple-brown.  Purple-brown aqueous starch/iod$ine$ tests for reducing agents by the reverse.