Objective: To prepare the diammonium glycyrrhizinate-loaded chitosan nanoparticles (DG-CS NPs), and evaluate its pharmaceutical properties and pharmacodynamic effects on ulcerative colitis (UC).

Methods: DG-CS NPs were prepared by spray drying method and optimized by orthogonal design. The morphology, size and in vitro release of DG-CS NPs were investigated. The therapeutic effects of DG-CS NPs on UC mice induced by dextran sulfate were evaluated preliminarily through disease active index method.

Results: The size of DG-CS NPs with loading capacity about (51.25 +/- 1.75)% was in the range of 300-600 nm. The release of DG-CS NPs was associated with environmental pH value and displayed significant therapeutic and preventive effects on UC.

Conclusions: DG-CS NPs prepared by spray drying method showed efficacy on UC mice.