A Facile Synthesis of LaFeO3-Based Perovskites and Their Application towards Sensing of Neurotransmitters

Lanthanum ferrite (LaFeO3) was prepared from its oxide precursors using solid state synthesis technique. Structural analysis indicate that the synthesized perovskite is phase pure having orthorhombic crystal structure with space group Pnma (62) and cell dimensions a=5.5392 angstrom, b=7.8573 angstrom, c=5.5584 angstrom. Morphological studies show aggregated spherical shaped nanoparticles having orthorhombic crystal structure with an average particle size of similar to 50 nm. The LaFeO3 modified glassy carbon electrode (GCE) was studied to determine its electrocatalytic activity towards dopamine oxidation. It is seen that the LaFeO3/GCE showed excellent electrocatalytic activity with a manifold increase in oxidation current compared to bare GCE. The sensing was carried out using Differential Pulse Voltammetry (DPV) wherefrom a detection limit of 10 nM and two linear regimes from 10 mu M to 100 mu M and 120 mu M to 180 mM was deduced. The influence of ascorbic acid and uric acid in the sensing of dopamine was investigated. The estimation of dopamine in human blood samples were analyzed with excellent recovery values.