Conjugation of tea catechins with chitosan nanoparticles

The conjugation of tea catechins (+)-catechin (C), (−)-epicatechin gallate (ECG) and (−)-epigallocatechin gallate (EGCG) with chitosan-15 and chitosan-100 kDa nanoparticles was studied in aqueous solution, using multiple spectroscopic methods, thermodynamic analysis and docking. Thermodynamic parameters showed that tea catechins bind nanoparticles via hydrophilic, hydrophobic and H-bonding contacts with larger polyphenols forming more stable conjugates with the order of EGCG > EGC > C. As chitosan size increased, the binding efficacy and stability of polyphenol-polymer adducts were increased. Chitosan nanoparticles are capable of delivery of tea catechins in vitro.