Sequential loading of inclusion complex/nanoparticles improves the gastric retention of Vladimiriae Radix essential oil to promote the protection of acute gastric mucosal injury

•A novel gastroretentive drug delivery system was developed of essential oil from Radix Aucklandiae by preparing the hydroxypropyl-β-cyclodextrin inclusion complex loaded into chitosan nanoparticles (V-CD/NPs).•V-CD/NPs showed a remarkable gastric retention performance.•Morphology and in vitro release profiles of V-CD/NPs had a pH-sensitivity.•V-CD/NPs exhibited a prominent protective effect on acute gastric mucosal injury induced by absolute ethanol for its anti-inflammatory and anti-oxidative stress effects comparable to cimetidine and the mucosal protection outperformed.