Selective Voltammetric Determination of Nitrite Using Cobalt Phthalocyanine Modified on Multiwalled Carbon Nanotubes

Nitrite (NO ₂ ⁻ ) is a ubiquitous inorganic pollutant presented in the food industry and drinking water. In addition, NO ₂ ⁻ as a toxic contaminant probably threaten human health by producing N-nitrosamines with highly carcinogenic. Voltammetric biosensing is considered the most promising approach because it offers a fast, reliable, and low-cost detection. In this article, cobalt (II) phthalocyanine (CoPc) was immobilized on multiwalled carbon nanotubes (MWCNTs), then immobilized on glassy carbon electrode (GCE) as an electrochemical senor toward nitrite using the voltammetric technique. Consequently, differential pulse voltammogram (DPV) is employed for nitrite determination, which reached a linear dynamic range of 0.01 to 1050.0 mM with a detection limit (LOD) of 2.11 μ M. Such excellent performance is ascribed to the synergistic effect between CoPc and MWCNT, indicating the promise of applying CoPc/MWCNTs@GCE in the practical bio-sensing applications.