The synthesis of thermo-sensitive antioxidant hydrogels by grafting of an antioxidant molecule and athermo-responsive monomer into inulin, in the presence of a crosslinker. In particular, catechin andNIPAAm, as antioxidant and thermo-responsive species, respectively, were inserted in a polymeric networkemploying a redox pair as an eco-friendly radical initiator system. Calorimetric, FT-IR, UV–Vis andfluorescence analyses were performed to verify both the formation of the inulin–antioxidant covalentbond and the insertion of bioactive molecules and monomers in the network. The hydrogels showed transitiontemperatures in the range 31.3–33.1 ◦C and a water affinity depending on the temperature of thesurrounding medium. The antioxidant activity of the conjugates was evaluated measuring the scavengerproperties of the hydrogels against the 2,2-diphenyl-1-picrylhydrazyl radical and the total flavonoid contentat different temperatures. The thermo-responsive antioxidant properties of the hydrogels confirmedthe efficiency of the proposed synthetic strategy and demonstrated as the antioxidant–carbohydratethermo-responsive conjugates possess peculiar features for specific applications in the food industry.
Innovative antioxidant thermo-responsive hydrogels by radical graftingof cathechin on inulin chain
Spizzirri G;Altimari I;PUOCI Francesco;Parisi OI;IEMMA Francesca;PICCI Nevio
2011-01-01
Abstract
The synthesis of thermo-sensitive antioxidant hydrogels by grafting of an antioxidant molecule and athermo-responsive monomer into inulin, in the presence of a crosslinker. In particular, catechin andNIPAAm, as antioxidant and thermo-responsive species, respectively, were inserted in a polymeric networkemploying a redox pair as an eco-friendly radical initiator system. Calorimetric, FT-IR, UV–Vis andfluorescence analyses were performed to verify both the formation of the inulin–antioxidant covalentbond and the insertion of bioactive molecules and monomers in the network. The hydrogels showed transitiontemperatures in the range 31.3–33.1 ◦C and a water affinity depending on the temperature of thesurrounding medium. The antioxidant activity of the conjugates was evaluated measuring the scavengerproperties of the hydrogels against the 2,2-diphenyl-1-picrylhydrazyl radical and the total flavonoid contentat different temperatures. The thermo-responsive antioxidant properties of the hydrogels confirmedthe efficiency of the proposed synthetic strategy and demonstrated as the antioxidant–carbohydratethermo-responsive conjugates possess peculiar features for specific applications in the food industry.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
