Novel Potentiometric Solid-contact Electrode for the Determination of Fe2+ Ions via MWCNTs-Gemifloxacin Composite

Abstract

A novel electrode was fabricated for the quantitation of Fe2+ ion. It was based on the covalent attachment of the gemifloxacin molecule (the recognition element) to the surface of MWCNTs to be incorporated as an electroactive material. Linear response of Fe2+ ions was found in the concentration range of 1×10−2 mol L−1 to 1×10−8 mol L−1 with a Nernstian slope of 30.37 ±0.3 (mV/decade) and attained a stable response within 5 s. The sensor exhibited LOD value of 4.8×10−9 mol L−1. It was applied in the monitoring of Fe2+ concentration in multi-vitamins tablets, tap water and milk samples with acceptable recovery ranged from 94.00 % to 102.00 %.