A novel potentiometric sensor based on a poly(anilineboronic acid)/graphene modified electrode for probing sialic acid through boronic acid-diol recognition

• A potentiometric sialic acid sensor is reported using PABA/ERGO composites.
• Preparation of composites by electrochemistry is a simple and a green method.
• The proposed sensor exhibits high sensitivity, high stability, and selectivity.
• High accuracy and good recoveries are obtained for analysis of serum samples.

A novel potentiometric approach was described for probing sialic acid (SA) using a poly(anilineboronic acid)/graphene modified glassy carbon (GC) electrode. The proposed electrode was prepared by electrodeposition of reduced graphene oxide (ERGO) at a GC electrode and then coated with a poly(anilineboronic acid) (PABA) film by electropolymerization of its monomer. Principle of SA detection at the PABA/ERGO/GC electrode was ascribed to a reversible and covalent boronic acid-diol binding which was sensitive to the electrochemical potential of the prepared sensor. The graphene layer introduced on the electrode surface was shown to dramatically improve the sensitivity of the sensor response. Under optimum conditions, the proposed sensor exhibited low detection limit of 0.8 μM with a wide linear range of 2 μM–1.38 mM, high stability, good regeneration, and remarkable selectivity. For the analysis of SA in human blood serum, the high accuracy and good recoveries revealed the great potential in the practical applications.