Poly(3-aminophenylboronic acid)-reduced graphene oxide nanocomposite modified electrode for ultrasensitive electrochemical detection of fluoride with a wide response range

Here we develop a novel approach for electrochemical detection of fluoride by poly(3-aminophenylboronic acid)-reduced graphene oxide (PAPBA-RGO) nanocomposite modified electrode. In this approach, the proposed electrode was fabricated by a two-step procedure, including direct electrodeposition of graphene oxide and electrochemical polymerization of 3-aminophenylboronic acid. Electrochemical detection of fluoride by PAPBA-RGO nanocomposite modified electrode was performed based on the variation of reduction peak current of ferricyanide, which was induced by the binding between boronic acid groups of PAPBA and fluoride. The obtained results displayed that reduction peak current of ferricyanide decreased with increasing concentration of fluoride, and two good linear relationships between the reduction peak current and the logarithm of fluoride concentration were obtained in the concentration range of 1   ×   10 −10 to 1   ×   10 −5   M and of 1   ×   10 −5 to 1   ×   10 −1   M, respectively. The limit of detection of the proposed approach was 9   ×   10 −11   M. The interference of other competing ions including Cl − , Br − , I − , NO 3 − , ClO 4 − , Ac − or SO 4 2− was negligible. Furthermore, the PAPBA-RGO nanocomposite modified electrode was employed for detection of fluoride in water samples.