In vitro study demonstrates that poly(vinyl alcohol) limits acid swelling and stabilizes chitosan cryogels, indicating potential for targeted oral delivery.
Key Points
To investigate how blending poly(vinyl alcohol) into chitosan cryogels impacts their microstructure, mechanical properties, and swelling performance across simulated digestive stages.
Fabricated chitosan cryogels combined with 0 to 5 wt% poly(vinyl alcohol) (PVA).
Characterized gel microstructure via SEM, bulk density, effective crosslinking density, and Young's modulus.
Assessed swelling kinetics and Weibull modeling across simulated gastric (pH 3.0) and intestinal fluids.
PVA incorporation increased bulk density, Young's modulus, and effective crosslinking density, though 5 wt% PVA triggered pore collapse and heterogeneity.
Under gastric conditions (pH 3.0), PVA lowered the 120-minute swelling ratio from 4.13 ± 1.13 down to 1.06 ± 0.29, with hydration shifting toward a slower equilibrium.
In the intestinal phase, unmodified chitosan cryogels displayed a dry mass gain shift from −0.28 ± 0.03 to 0.22 ± 0.20, pointing to the entrapment of digestive fluids.