Synergistic modulation of chitosan on the mechanical and disintegration properties of pre-gelatinized waxy corn starch orally disintegrating film

Abstract

The inconsistency between good mechanical properties and rapid disintegration characteristic is a challenge for starch-based orally disintegrating films (ODF). In order to improve the mechanical and disintegration performances of the films, chitosan/pre-gelatinized waxy corn starch (PWCS) ODF was fabricated and investigated for physical properties, surface micromorphology and crystallinity. The results showed that the mechanical properties of the composite films were improved (6.55 MPa ± 1.22 MPa, 18.11% ± 2.34%) while the fast disintegration characteristic (<30 s) was still maintained. During the film-forming process, the retrogradation of PWCS chains was hindered by chitosan molecules and the polar groups were exposed, enhancing the plasticity and hydrophilicity of the composite films. There was a synergistic effect between chitosan and PWCS. In addition, the microscopic images indicated that the high compatibility of chitosan and PWCS caused a homogeneous surface for the composite films. However, PWCS aggregated when the concentration of chitosan exceeded 20%, which increased the short-range order and crystallinity of PWCS in the composite films. The study provided a theoretical feasibility for the development of novel oral carrier platform.