In recent years, novel electrocatalytic materials have been proposed for developing more sensitive, simple, stable, and low-cost nonenzymatic electrochemical sensors. In this regard, in previous works [1,2] we reported the promising characteristics of various perovskite nanomaterials as electrocatalytic modifiers for screen printed carbon electrode (SPCE). Perovskite ferrite oxides exhibits fascinating properties for electrochemical sensing due to the ability of the perovskite structure to accommodate different metallic ions. Here, we reported a study in developing an electrochemical dopamine sensor (DA), an important brain neurotransmitters, based on NdFeO3. NdFeO3 nanoparticles, of approximately 28 nm in size, were synthesized by a simple thermal treatment method [3] as follows: metal nitrates with equal molar ratios were added to poly(vinyl alcohol (PVP) solution while the temperature of solution was kept at 90 ˚C for 2 hours. The mixed solution was placed in oven (100 ˚C) for 24h. The solid product formed was crushed, ground in a mortar to form a soft powder and finally annealed at 700˚C (in air for 3 h) for decomposing organic compounds and favor particle crystallization (Fig 1a). Perovskite nanopowders were largely characterized by complementary physical and chemical techniques. SPCE electrodes modified with NdFeO3 nanoparticles were fabricated (inset Fig. 1a) and tested by cyclic voltammetry. The modified electrode exhibited a pair of redox peaks (Fig. 1b) in which the anodic peak potential is significantly shifted to lower potential compared to bare SPCE, indicating a strong promoting effect toward the electrochemical oxidation of dopamine. Moreover, the peak current of NdFeO3-SPCE sensor is more than 2 times higher than of bare SPCE (Fig. 1c). demonstrating high sensitivity to DA, good linear range from 0.1 μM to 500 μM and low detection limit. The modified sensor, operating in amperometric mode at the potential of 0.2 V, exhibited rapid response, and anti-
