Abstract: The plant-type capsule shell can overcome many shortcomings of the commercially available gelatin capsule shell, such as water-resistance hardening, water absorption softening, difficult source control, poor patient compliance, etc., and has a good development prospect. In this experiment, plant polysaccharide capsule shells were prepared by using Astragalus polysaccharide as a film-forming material, and quality evaluation was carried out.Taking the moisture permeability of the free film of Astragalus polysaccharide and the cysticity of capsule shell as the evaluation index, the quality of Astragalus polysaccharide, the type of hydroxypropyl methylcellulose, the quality of hydroxypropyl methylcellulose, glycerin and the effect of volume on the capsule shell of Astragalus polysaccharides were investigated by single factor experiment and orthogonal design experiment; friability, tightness and in vitro release were evaluated. According to the data, the optimal prescription of Astragalus polysaccharide capsule shell
is 0.75 g of Astragalus polysaccharide, 150,000 mPa?s of hydroxypropyl methylcellulose, 1.3 g of hydroxypropyl methylcellulose, 2.0 mL of glycerol, and homemade capsule shell. The friability and tightness meet the requirements of the pharmacopoeia; the moisture permeability of the free film of Astragalus polysaccharide prepared under these conditions is g?mmm-2?h-1?kPa-1, which is low; the capsule shell has a cystic score of 11 points, so the cysticity is good. The self-made capsule shell has the friability and tightness in accordance with the requirements of the pharmacopoeia, and the in vitro release test shows that it has a sustained release effect.

Key words: Polysaccharide capsule shell, prescription optimization, quality evaluation