Related Experiment Video
Updated: Mar 20, 2026

Preparation and Characterization of SDF-1α-Chitosan-Dextran Sulfate Nanoparticles
Published on: January 22, 2015
pH and temperature stability of (-)-epigallocatechin-3-gallate-β-cyclodextrin inclusion complex-loaded chitosan
Fei Liu1, Hamid Majeed2, John Antoniou2
1State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China; Western Regional Research Center, ARS, U.S. Department of Agriculture, Albany, CA 94710, United States.
Abstract:
The oxidative stability of (-)-epigallocatechin-3-gallate (EGCG) incorporated as inclusion complexes (ICs) in sulfobutylether-β-cyclodextrin sodium (SBE-β-CD) and then ionotropically crosslinked with chitosan hydrochloride (CSH) into nanoparticles were investigated. EGCG-loaded CSH-SBE-β-CD nanoparticles (CSNs) were physically unstable at higher pH and temperature. The particle size of CSNs was unchanged in the pH range of 3-5, but the microenvironment of EGCG-IC appeared to be intact until the pH increased to 6.5 by fluorescence spectroscopy. The physical structure of EGCG-ICs was also affected during storage in addition to CSNs, which was further affected as temperature increased from 25 to 55°C. The decrease in antioxidant activities of EGCG-ICs and free EGCG with increasing pH, storage time and temperature were modest compared to the prominent decreases in antioxidant activities of EGCG-loaded CSNs. The extreme entrapment of EGCG-ICs and/or free EGCG in the aggregated CSNs restricted the release of EGCG, thus inhibiting the antioxidant activities.
More Related Videos
Related Concept Videos
Bioavailability Enhancement: Drug Stability Enhancement and GI Retention
Complexation Equilibria: The Chelate Effect
Stability of Substituted Cyclohexanes
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
Complexation Equilibria: Factors Influencing Stability of Complexes
Factors Affecting Dissolution: Drug Permeability, Stability and Stereochemistry

