Solvent-Dependent Catalytic Behavior of Hydrophobic Guest Artificial Glutathione Peroxidase Determined Using H2O2 and 4-Nitrobenzenethiol as Substrates

Using H2O2 and 4-nitrobenzenethiol as substrates, the catalytic behavior of a hydrophobic guest artificial glutathione peroxidase (GPx) (ADA-Te-ADA) was detailed investigated. The relation between the catalytic rate of ADA-Te-ADA and the property of solvent used in the determination of catalytic rate was revealed. Typically, Ethanol, DMSO, DMF and CH3CN were selected as the co-solvents in the determination of catalytic rates. It indicated that ADA-Te-ADA exhibited the typical solvent-dependent catalytic behavior. Especially, the higher catalytic rate was observed when polar protic solvent (ethanol) was used compared with other co-solvents. It suggested that polar protic solvent was the appropriate co-solvent for the assay of catalytic activity of hydrophobic artificial GPx. Additionally, the strong polarity of polar aprotic solvent plays an important role in the enhancement of GPx catalytic activity. This study bodes well for the understanding of the catalytic behavior of hydrophobic guest artificial GPx .