Comparative study of normal, micro- & nano-sized iron oxide effect in potentiometric determination of fluconazole in biological fluids

Abstract

Three novel fluconazole (FLU) selective electrodes were investigated with di-octyl phthalate as a plasticizer in a polymeric matrix of polyvinyl chloride and 2-hydroxypropyl-β-cyclodextrin as an ionophore. The potentiometric strategy was based on functionalized magnetic iron oxide particles. A mixture of equal volumes of 1 × 10⁻² M FLU and 1 × 10⁻² M KCl was used as an internal reference solution for sensor 1. An aqueous dispersion of magnetic micro iron oxide particles was introduced into an internal reference solution for sensor 2, whereas an aqueous dispersion of magnetic nano iron oxide particles was introduced for sensor 3. By applying a magnetic field, the iron oxide particles could be attached to the surface of an ionophore-free polymeric membrane. FLU was accurately determined in spiked human plasma and spiked cow milk.