For the first time, lanthanum cobalt oxide was prepared in a rose like structure and assisted with functionalized carbon nanofiber (f-CNF/LaCoO3) using the hydrothermal technique. Further, the prepared f-CNF/LaCoO3 was used as an electrode material for sensitive electrochemical detection of non-steroid anti-inflammatory drug 4-Aminoantipyrine (4-AAP). The formation of f-CNF/LaCoO3 nanocomposite was characterized by using various analytical techniques including scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). In addition, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and amperometric i-t technique were performed to scrutinize the electrochemical activity of f-CNF/LaCoO3/GCE toward the electrochemical oxidation of 4-AAP. The proposed sensor exhibits excellent electrochemical performance with wide linear range (0.001e1374.87 mu M) and ultra low detection limit of as low as concentration (1.0 nM) of 4-AAP. Moreover, the excellent selectivity of the sensor was recorded and the practicability of the sensor also demonstrated for detection of 4-AAP in the human urine sample. (C) 2017 Elsevier Ltd. All rights reserved.