A 6A,6A¢-dicyclohexylamine-6B,6B¢-diselenide-bis-b-cyclodextrin (6-CySeCD) was designed and synthesized to imitate the antioxidant enzyme glutathione peroxidase (GPX). In this novel GPX model,b-cyclodextrin provided a hydrophobic environment for substrate binding within its cavity, and a cyclohexylamine group was incorporated into cyclodextrin in proximity to the catalytic selenium in order to increase the stability of the nucleophilic intermediate selenolate.