Abstract:IIn this study, essential oil was extracted from sweet basil through steam distillation, its components were analyzed by GC-MS, and its antioxidant activity was preliminarily explored in vitro. Utilizing sweet basil essential oil (EO) as the core material and chitosan (CS) as the wall material, chitosan nanoparticles loaded with sweet basil essential oil (CSNPs-EO) were fabricated via ionic crosslinking. The optimal preparation conditions for CSNPs-EO were ascertained using response surface methodology, and the morphological characteristics of CSNPs-EO were delineated. The experimental findings revealed that the principal constituents of EO were terpenes and phenylpropanoid derivatives, encompassing linalool (21.16%), eugenol (20.83%), τ-cadinol (8.63%), and cineole (6.60%). EO demonstrated potent scavenging capabilities against both DPPH and ABTS radicals, with IC50 values of 0.407 mg·mL?1 and 0.355 mg·mL?1, respectively. The optimal preparation parameters for CSNPs-EO included a chitosan solution pH of 4.70, a core-to-wall ratio of 1.0, and a TPP solution concentration of 2.95%. Under these conditions, the embedding efficiency reached 71.14%, and the drug loading capacity was 41.56%. TEM and DLS analyses indicated that CSNPs-EO possessed a nearly spherical core-shell architecture, with an average particle diameter of 178.1 nm, a polydispersity index (PDI) of 0.163, and a zeta potential of 39.1 mV. Sweet basil essential oil exhibits remarkable antioxidant activity, and CSNPs-EO prepared through ionic crosslinking display uniform particle size distribution and favorable stability.