Development of a highly sensitive electrochemical sensor based on a recently synthesized MOF for the determination of Pb2+ in food samples at ultra-trace levels using box-Behnken design
Microchemical Journal, vol.219, 2025 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 219
- Publication Date: 2025
- Doi Number: 10.1016/j.microc.2025.115961
- Journal Name: Microchemical Journal
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, Chimica, Index Islamicus
- Keywords: Anodic stripping square wave voltammetry, Box-Behnken experimental design, Electrochemical sensor, Metal organic framework, Pb2+
- Open Archive Collection: Article
- Azerbaijan State University of Economics (UNEC) Affiliated: Yes
Abstract
This study concentrated on designing an electrochemical sensor based on a metal-organic framework (MOF) composed of zinc (II), 4-methyl-1,2,4-triazole-3-thiol, and ethylenediamine ligands (ZMTE-MOF). The ZMTE-MOF was characterized using several analytical methods, including electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). After synthesis, the ZMTE-MOF was employed in the creation of an anodic stripping square wave voltammetric electrochemical sensor for detecting ultra-trace levels of Pb2+ ions. Experimental parameters were initially screened using a Plackett-Burman design, followed by further refinement through a Box-Behnken optimization approach. Optimal conditions were determined to include a ZMTE-MOF concentration of 1.31 mg mL−1, a pH of 2.57, a deposition potential of −1.03 V, and a deposition time of 200 s. Under these settings, the sensor demonstrated a linear detection range for Pb2+ concentrations spanning 1.00–200.00 nmol L−1, with a detection limit as low as 0.03 nmol L−1. The sensor exhibited excellent repeatability, satisfactory reproducibility, and remarkable selectivity for Pb2+. Its performance was further validated by testing it on ten different edible samples. The results obtained were cross-verified with inductively coupled plasma mass spectrometry (ICP-MS), serving as the standard reference method, and a t-test confirmed the sensor's reliability and effectiveness.