Composite film preparation

Acidic solutions of chitosan (2%, 2 ml) and gelatin (2%, 2 ml) were prepared separately by dissolving in acetic acid (1%, v/v) and then were mixed together in 1:1 proportion. This mixture was stirred for 4 h at room temperature and the homogeneous blend was then spread uniformly on a glass plate (9 cm²) and kept overnight in a dust-free hood for drying. The composite film of biopolymers, thus obtained was stored at 4°C under dry conditions and was rinsed with phosphate buffer (0.1M, pH 8.0) before use (Tembe et al., 2006).