Design of a Graphite/Zinc Nanoparticles/1-nitroso-2-naphthol Voltammetric Substrate for the Measurement of Magnesium in Human Serum Samples

In this research, a voltammetric substrate with a graphite/zinc nanoparticles/1-nitroso-2-naphthol structure has been developed to measure magnesium in human blood serum. Zinc nanoparticles and 1-nitroso-2-naphthol were deposited on the surface of a bare graphite electrode using the cyclic voltammetry technique. The formation of nanostructured layers on the graphite electrode surface was confirmed using scanning electron microscopy. The voltammetric platform created with the graphite/zinc nanoparticles/1-nitroso-2-naphthol structure serves as an electrochemical sensor that exhibits satisfactory electrocatalytic properties, with an electron transfer coefficient (α of 0.75), an apparent charge transfer rate constant (log ks = 3.27), and an active layer concentration on the modified electrode surface of (5.16 ×10^-5). Notable features of the proposed sensor include high sensitivity, a low limit of detection (LOD) of 8.31 nM, a limit of quantification (LOQ) of 24.87 nM, and a wide linear range (25 to 250 nM). Additionally, the modified electrode with the graphite/zinc nanoparticles/1-nitroso-2-naphthol configuration demonstrates stability, repeatability, selectivity, and acceptable measurement accuracy in the square wave voltammetric evaluation of magnesium in human blood serum