Elsebai et al. 2023 — Amperometric mercury sensor with organic chelator ionophore
This paper from the University of Coimbra and National Research Centre (Egypt) describes a novel amperometric electrochemical sensor for mercury ion (Hg2+) detection. The sensor uses an organic chelator ionophore (N,N-di(2-hydroxy-5-[(4-nitrophenyl)diazenyl]benzaldehyde)benzene-1,2-diamine, NDBD) combined with multiwalled carbon nanotubes (MWCNT) immobilized on a glassy carbon electrode. The sensor achieves a linear response for Hg2+ in the range of 1 to 25 µM with a detection limit of 60 nM, and demonstrates excellent selectivity towards Hg2+ over other heavy metal ions. The method was validated in both water and milk sample matrices.
Note: the triage manifest assigned this paper a year of 1972, which is incorrect; the paper was published in Molecules 2023 (DOI confirmed from text).
Key numbers
- LOD: 60 nM Hg2+ (approximately 12 µg/L)
- Linear range: 1 to 25 µM
- Selectivity: excellent over interfering heavy metal ions (tested Cd2+, Pb2+, Cu2+, Zn2+, Ni2+, Co2+, Fe3+, Mg2+, Ca2+)
- Applied to: milk samples and water samples (validation; no quantitative contamination data reported)
Methods (brief)
Amperometric sensor using NDBD organic chelator ionophore and MWCNT on glassy carbon electrode. Parameters optimized: ionophore concentration, applied potential, electrolyte pH. Applied potential determines selectivity between mercury and other metals. Detection in aqueous solution.
Implications
Certification: Not applicable for threshold setting; no food contamination concentration data. Courses: Relevant to electrochemical sensor module; illustrates ionophore-based selectivity approach for Hg2+ in food matrices. App: Not applicable (no food concentration data).