Related Experiment Video
Updated: Dec 20, 2025
Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
Effect of porcine pancreatic α-amylase on dexamethasone release from aqueous solution containing natural
Suppakan Sripetch1, Phatsawee Jansook2, Thorsteinn Loftsson1
1Faculty of Pharmaceutical Sciences, University of Iceland, Hofsvallagata 53, 107 Reykjavik, Iceland; Oculis ehf, Alfheimar 74, 6th Floor, 104 Reykjavik, Iceland.
Abstract:
Dexamethasone release from natural γ-cyclodextrin (γCD) complexes was investigated in presence of porcine pancreatic α-amylase (PPA). The phase-solubility of dexamethasone in aqueous γCD solutions was determined, PPA degradation of γCD was investigated, and permeation studies were performed in simulated tear fluid. The phase-solubility profile was of Bs type and the stability constant (K1:1) of the dexamethasone/γCD complex determined from the initial linear section of the profile was relatively high or 12887 M-1. The high K1:1 value indicates that dexamethasone has high affinity for γCD under the test condition. From the PPA catalyzed γCD degradation studies the Michaelis-Menten constant (Km) and Vmax were determined to be 3.24 mM and 9.79 × 10-3 mM/min, respectively. The permeation studies performed at low γCD concentrations, showed that dexamethasone is released from the complex solutions at faster rate when PPA was present than when no PPA was present.
