Sorption Properties of Sunflower Husk Melanins

Abstract

The sorption properties of sunflower husk melanins were studied according to pharmacopoeial monograph GPM.1.2.3.0021.15 using marker compounds methylene blue, methyl orange, gelatin, and iodine. The sorption capacities of the studied samples were found to be 190.9 ± 4.2 mg/g for methylene blue; 302.1 ± 1.8, methyl orange; 114.7 ± 2.8, gelatin; and 38.4 ± 2.4%, I₂ . The sorption capacities of the samples were greater than those of the sorbents Polifepan and Polysorb and comparable with that of activated charcoal for medium-molecular-mass toxicants. The melanins showed high affinity for anionic substances. The protein-binding capacities of the melanins were inferior only to that of Polysorb and significantly greater than those of Polifepan and activated charcoal. The sorption capacity for I₂ matched that of Polifepan and was >1.5 times less than that of activated charcoal. The results showed that enterosorbents based on melanins could be developed.