One-pot preparation of uricase-poly(thiophene-3-boronic acid)-Pt_(nano) composites for high-performance amperometric biosensing of uric acid

摘要

Chemical oxidation of glycoprotein-bound thiophene-3-boronic acid (TBA) monomer by relatively mild oxidant chloroplatinate in neutral aqueous solution containing uricase yielded uricase-PTBA-Pt_(nano) bio-nanocomposite with high enzymatic specific activity on a platinized (Pt_(plate)) Au electrode, which was then covered by an outer-layer chitosan (CS) film to fabricate a CS/uricase-PTBA-Pt_(nano)/Pt_(plate)/Au electrode. This electrode exhibited a linear amperometric response to uric acid concentration from 5 μM to 1.2mM with a sensitivity of 134μAmM~(-1) cm~(-2), a limit of detection (S/N=3) of 1 μM, and excellent operation/storage stability, which also worked well in serum samples.