Oxygen → Hydrogen Peroxide

Participants

Reaction Steps

The NPs were removed by washing the tube. Next, a second cycle of ML was performed to protect the GOx binding sites by magnetic NPs using a multi-peg magnet that induced the magnetic field at the GOx binding sites. Then, the covalent coupling of HRP to amino propyl silane was performed by injecting buffer solution (e.g. 0.05M HEPES buffer solution) containing 0.3 mg ml−1 HRP (RC. 1.11.1.7) in the presence of EDC (e.g. 0.01 M EDC with an incubation time of 2 h at room temperature). Consequently, the HRP covalently bound to the amine groups, which are located in-between GOx binding sites. The sequential enzymatic reaction in the tube was initiated by injecting to the tube glucose with 2,2,5,5′ tetramethyl-benzidine (TMB). TMB was dissolved in ethanol then diluted with 0.1M buffer phosphate pH 6.0 with 50 mM glucose to yield the glucose solution that includes 1 mM TMB and 2%(v/v) ethanol. The glucose was oxidized by the GOx and O2 to yield gluconic acid and H2O2. The H2O2 diffused to the HRP binding sites and there the HRB biocatalyzed the oxidation of TMB by H2O2, yielding an insoluble product.

Provenance & Evidence