In this work, bimetallic alloyed AuPd nanorod chains (NRCs) were synthesized by a rapid and simple one-step wet-chemical method, using 4-aminopyridine (4-AP) as the structure director and stabilizing agent, while no any seed, polymer or surfactant was involved during the synthetic process. The architecture was characterized by transmission electron microscopy (TEM) and high-resolution TEM, high-angle annular dark-field scanning TEM (HAADF-STEM), energy-dispersive X-ray spectrometer (EDS) patterns and EDS line scanning profiles, X-ray diffraction, and X-ray photoelectron spectroscopy. An amperometric sensor for hydrazine detection was constructed, and exhibited wide linear range of 0.10-501.00 mu M and low detection limit (S/N = 3) of 0.02 mu M with ultra-high sensitivity, revealing the improved electroanalytical performance for hydrazine determination. (C) 2016 Elsevier Ltd. All rights reserved.