Preparation and Characterization of Oxidized Corn Starch/Gelatin Composite Hard Capsules

ABSTRACT Gelatin (Ge) is expensive and using modified starch to partially replace Ge to prepare composite hard capsules can significantly reduce the cost of hard capsules. In this study, the oxidized corn starch (OSt) and Ge were used as raw materials to prepare composite hard capsules by the impregnation method. The effects of starch oxidation degree and oxidized starch/Ge ratio on the properties of composite capsule‐film and hard capsule were studied and were also characterized by Fourier transform infrared spectroscopy (FTIR), x‐ray diffraction (XRD), and scanning electron microscopy (SEM). The results showed that OSt and Ge could be miscible into a uniform gel solution system. When the ratio of OSt to Ge was 5:5, the water content of the capsule‐film was 10.5%–13.0%, and the prepared hard capsule was completely dissolved in artificial gastric juice within 10 min, which met the requirements of the Chinese Pharmacopoeia (2020). The OSt is cheaper than Ge and can replace half of the Ge to prepare OSt/Ge composite hard capsules, which greatly reduced the cost of the hard capsules.