title: FeMoO4 based, enzyme-free electrochemical biosensor for ultrasensitive detection of norepinephrine.
abstract: Herein, FeMoO4 (FM) nanorods were synthesized by a template-free, facile, hydrothermal method in an aqueous medium. The surface morphology of FeMoO4 was identified with field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). X-ray diffraction (XRD) was performed to identify the crystallographic nature of the as-synthesized FeMoO4. The as-synthesized material was used as an active electrode material for the oxidation of a neurotransmitter (i.e. norepinephrine (NE)) by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. FeMoO4 possesses polycrystallanity and bimetallic character, which helps to enhance the performance of the FM/GCE as compared to the GCE. The enhanced performance was also due to the formation of Fe (II)-dioxygen complexes, which catalyze the oxidation of NE. Meticulous observations taken from CV studies proved the diffusion-controlled nature of the reaction with a diffusion coefficient of 1.10×10(-4)cm(2)/s and a standard heterogeneous rate constant of 4.078×10(-3)cm/s. The amperometric response of NE on the FM/GCE showed a linear increase in the current between 5.0×10(-8)M and 2.0×10(-4)M with a detection limit of 3.7×10(-9)M. In the amperometric study, the time required to reach the 98% steady state response, after successive additions of 50nM NE, was less than 3s. The FM/GCE showed good sensitivity, and stability for the determination of NE.
authors.affiliation: Department of BIN Convergence Technology, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea.
authors.forename: Kunda J
authors.initials: KJ
authors.lastname: Samdani
authors.affiliation: Department of BIN Convergence Technology, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea.
authors.forename: Jitendra S
authors.initials: JS
authors.lastname: Samdani
authors.affiliation: Department of BIN Convergence Technology, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea.
authors.forename: Nam Hoon
authors.initials: NH
authors.lastname: Kim
authors.affiliation: Department of BIN Convergence Technology, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea; Center for Carbon Composites Materials, Department of Polymer & Nano Science and Technology, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea. Electronic address: jhl@jbnu.ac.kr.
authors.forename: Joong Hee
authors.initials: JH
authors.lastname: Lee
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000032:analysis*; D015374:Biosensing Techniques / Q000379:methods; D055664:Electrochemical Techniques / Q000379:methods*; D058085:Iron Compounds / Q000737:chemistry*; D057230:Limit of Detection; D008982:Molybdenum / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D009638:Norepinephrine / Q000032:analysis*; D010084:Oxidation-Reduction
chemical_list: D000316:Adrenergic alpha-Agonists; D058085:Iron Compounds; C044659:molybdate; D008982:Molybdenum; D009638:Norepinephrine
keywords: Biosensor; Electrochemical; Fe (II)-Dioxygen complex; FeMoO(4); Nanorods; Norepinephrine