ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Comparison of the modification of graphite electrodes with poly(4-aminobenzoic acid) and poly(4-hydroxyphenylacetic acid) for determination of Pb(II)

Marina F. F. Matos, Priscila I. Soares, Thaís M. Lima, Arnaldo C. Pereira, Diego L. Franco, and Lucas F. Ferreira

Institute of Science and Technology, Federal University of the Jequitinhonha and Mucuri Valleys, UFVJM, Diamantina, Brazil

E-mail: lucas.franco@ict.ufvjm.edu.br

Received: 10 March 2022  Accepted: 12 May 2022

Abstract:

In this work, we investigate and characterize graphite electrodes (GE) modified with polymeric films derived from 4-hydroxyphenylacetic acid (4-HPA) and 4-aminobenzoic acid (4-ABA) for the determination of the Pb(II) in water samples by square-wave anodic stripping voltammetry (SWASV). The electropolymerization was carried out in acid and basic medium using cyclic voltammetry (CV). The platform with poly(4-ABA) showed higher sensitivity for Pb(II) detection. Then, we performed the optimization of the electropolymerization parameters of 4-ABA where the better electrochemical responses were obtained at a monomer concentration of 0.25 mM with 25 cycles at 25 mV s⁻¹ in the basic media. The modified electrodes showed a decrease in the CV response in a ferricyanide/ferrocyanide potassium solution, and an increase in the charge transfer resistance (R_ct) values is obtained by impedance spectroscopy electrochemistry (EIS). The calibration curve obtained for Pb(II) detection showed a linear range from 50 to 3224 µg L⁻¹, with a limit of detection of 13.7 µg L⁻¹ and a limit of quantification of 45.6 µg L⁻¹. Addition and recovery studies showed levels of 94.5%. No detectable levels of Pb(II) under the established conditions were observed in water samples. Therefore, the investigated sensor using poly(4-ABA) is promising for Pb(II) detection in water samples.

Graphical abstract

Keywords: Modified electrodes; Electrochemical detection; poly(4-aminobenzoic acid), Polymeric films; Lead; Square-wave anodic stripping voltammetry

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-022-02282-1

Chemical Papers 76 (9) 5691–5704 (2022)