Zr-MOF Nanospheres\non Zn-MOF Nanorods on Ni Foam for\nthe Electrochemical Detection of Ivermectin in Urine Samples

Ivermectin (IVM) is a broad-spectrum antiparasitic drug\nwidely\nused in human medicine with established uses in treating various parasitic\ninfections. This study introduces Zr (zirconium)-metal–organic\nframework (MOF) nanospheres on Zn (zinc)-metal–organic framework\n(MOF) nanorods on nickel foam (NF) as an advanced electrochemical\nsensor for detecting IVM in simulated urine samples. We synthesized\nZr-MOF nanospheres and Zn-MOF nanorods and then coated the spheres\nwith rods using ultrasonication to form Zr-MOF on Zn-MOF. This approach\nenhances the electrochemical properties by leveraging the distinct\ncharacteristics of each MOF component. These nanostructures are meticulously\ncharacterized using transmission electron microscopy (TEM) to determine\nthe morphology of the sensor. The valence states of Zr-MOF on Zn-MOF\nare investigated utilizing XPS (X-ray photoelectron spectroscopy),\nand X-ray diffraction (XRD) has validated the material’s crystalline\nnature. The resulting Zr-MOF on Zn-MOF/NF sensor demonstrates a wide\nlinear range of detection (1 nM to 5 μM) with a sensitivity\nof 0.075 mA/nM.cm<sup>–2</sup> and a lower detection limit\n(LOD) of 1.75 nM (= 3s/m). This sensor is highly selective over other\ninterfering species such as urea, uric acid (UA), glucose, sucrose,\nand ions such as Na<sup>+</sup>, K<sup>+</sup>, Cl<sup>–</sup>, SO<sub>4</sub><sup>2–</sup>, and Ca<sup>2+</sup>. The differential\npulse voltammetry (DPV) technique reveals effective real-time detection\ncapabilities in simulated urine samples. The Zr-MOF on Zn-MOF nanostructures\noffer a significant advancement in electrochemical sensing due to\ntheir enhanced conductivity and expanded active surface area, making\nthem a promising material for sensitive and selective analyte detection.\nThis sphere and rod configuration demonstrates a superior electrochemical\nperformance, highlighting its potential for applications in advanced\nsensing technologies. Future research could further explore its capabilities\nin detecting a wider range of biomolecules and its integration into\nclinical diagnostics and biomedical applications.