“…Quercetin, rutin (a glycoside of quercetin), morin (a structural isomer of quercetin), and taxifolin (a reduced form of quercetin) were used as flavonoid components for the combinations (see Figure 1 ). These flavonoids are well-known natural antioxidants whose potential health benefits have attracted a great deal of interest in their studies as prospective drugs [ 7 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 ]. Thus, a large and growing body of literature has been devoted to the modification of their biopharmaceutical and physicochemical properties, such as antioxidant activity and bioavailability, by crystal engineering [ 40 , 41 , 42 , 43 , 44 ], obtaining solid dispersions [ 45 , 46 , 47 , 48 , 49 ], and the development of new polymorphic forms [ 50 , 51 , 52 , 53 , 54 ].…”