Doan et al. (2025) develop an electrochemical sensor for lead(II) (Pb2+) detection based on a composite of a bimetallic metal-organic framework (FeMg-BDC MOF) and reduced graphene oxide (rGO) deposited on a glassy carbon electrode. The MOF/rGO composite provides enhanced surface area and electrochemical activity for sensitive Pb2+ stripping analysis.
Key numbers
Limit of detection (LOD): 9 ng/L (9 ppt, or 0.009 µg/L) for Pb2+ in water. This is well below the US EPA action level for lead in drinking water (15 µg/L) and the EU parametric value (5 µg/L since 2021, with a transition to 5 µg/L), and also below the WHO guideline of 10 µg/L. A LOD of 9 ng/L is analytically competitive with ICP-MS for environmental water.
Validated in tap water and river water. No food matrix validation.
Methods (brief)
Differential pulse anodic stripping voltammetry (DPASV) at MOF/rGO modified GCE. Preconcentration step accumulates Pb onto the electrode surface before stripping. Sub-10 ng/L LOD demonstrates the sensitivity advantage of stripping voltammetry for Pb in water matrices.
Implications
Testing: The 9 ng/L LOD is exceptional for an electrochemical method and competitive with ICP-MS. This type of sensor platform could support field deployment for drinking water monitoring. Not applicable to food matrices directly without further method development and validation.