Facile synthesis of large area pebble-like β-NaFeO2 perovskite for simultaneous sensing of dopamine, uric acid, xanthine and hypoxanthine in human blood

Here, we report a facile one-step solid-state reaction assisted synthesis of beta-NaFeO2 perovskite for simultaneous sensing of Dopamine (DA), Uric Acid (UA), Xanthine (Xn) and Hypoxanthine (Hxn) in human blood. The orthorhombic phase formation in beta-NaFeO2 with the presence of octahedral sites is confirmed through x-ray diffraction (XRD) and Raman spectroscopy while high surface area pebble-like morphology is observed through scanning electron microscopy (SEM). The sensor exhibits distinct oxidation potentials for DA, UA, Xn and Hxn with a peak separation (AEp) between DA-UA, UA-Xn and Xn-Hxn as 134 mV, 388 mV and 360 mV, respectively. The sensor exhibits an excellent selectivity, sensitivity and low limits of detection (LOD) of 2.12 nM, 158 nM, 129 nM and 95 nM for DA, UA, Xn and Hxn, respectively which are well below the lower limits of their presence in physiological ranges in human body fluids. The sensor shows an excellent selectivity and it was successfully employed in simultaneous sensing of DA, UA, Xn and Hxn in simulated blood serum samples with excellent recovery percentages. This is the first report on low-cost beta-NaFeO2 modified GCE for simultaneous electrochemical sensing of biomolecules which can be applied for numerous bioanalytical applications.