title: Direct electrochemistry and electrocatalysis of lobetyolin via magnetic functionalized reduced graphene oxide film fabricated electrochemical sensor.
abstract: A novel lobetyolin electrochemical sensor based on a magnetic functionalized reduced graphene oxide/Nafion nanohybrid film has been introduced in this work. The magnetic functionalized reduced graphene oxide was characterized by fourier transform infrared spectroscopy, atomic force microscope, X-ray diffraction, transmission electron microscopy and thermogravimetric analysis. The scanning electron microscopy characterized the morphology and microstructure of the prepared sensors, and the electrochemical effective surface areas of the prepared sensors were also calculated by chronocoulometry method. The electrochemical behavior of lobetyolin on the magnetic functionalized reduced graphene oxide/Nafion nanohybrid modified glassy carbon electrode was investigated by cyclic voltammetry and differential pulse voltammetry in a phosphate buffer solution of pH6.0. The electron-transfer coefficient (α), electron transfer number (n), and electrode reaction rate constant (Κs) were calculated as 0.78, 0.73, and 4.63s-1, respectively. Under the optimized conditions, the sensor based on magnetic functionalized reduced graphene oxide/Nafion showed a linear voltammetric response to the lobetyolin concentration at 1.0×10-7to 1.0×10-4mol/L with detection limit (S/N=3)of 4.3×10-8mol/L. The proposed sensor also displayed acceptable reproducibility, long-term stability, and high selectivity, and performs well for analysis of lobetyolin in real samples. The voltammetric sensor was successfully applied to detect lobetyolin in Codonopsis pilosula with recovery values in the range of 96.12%-102.66%.
authors.affiliation: School of Pharmacy, Lanzhou University, Lanzhou 730000, China.
authors.forename: Bolu
authors.initials: B
authors.lastname: Sun
authors.affiliation: School of Chemistry and Chemical Engineering, Nanjing University, 210046, China.
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Gou
authors.affiliation: School of Pharmacy, Lanzhou University, Lanzhou 730000, China.
authors.forename: Ruibin
authors.initials: R
authors.lastname: Bai
authors.affiliation: School of Pharmacy, Lanzhou University, Lanzhou 730000, China.
authors.forename: Ahmed Attia Ahmed
authors.initials: AAA
authors.lastname: Abdelmoaty
authors.affiliation: School of Pharmacy, Lanzhou University, Lanzhou 730000, China.
authors.forename: Yuling
authors.initials: Y
authors.lastname: Ma
authors.affiliation: School of Pharmacy, Lanzhou University, Lanzhou 730000, China.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Zheng
authors.affiliation: School of Pharmacy, Lanzhou University, Lanzhou 730000, China. Electronic address: hufd@lzu.edu.cn.
authors.forename: Fangdi
authors.initials: F
authors.lastname: Hu
mesh_terms: D015374:Biosensing Techniques; D002384:Catalysis; D029745:Codonopsis / Q000737:chemistry / Q000378:metabolism; D055664:Electrochemical Techniques; D004566:Electrodes; D052203:Ferrosoferric Oxide / Q000737:chemistry; D005465:Fluorocarbon Polymers / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D008280:Magnetics; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D010087:Oxides / Q000737:chemistry; D053279:Polyynes / Q000032:analysis*; D015203:Reproducibility of Results; D013818:Thermogravimetry; D014961:X-Ray Diffraction
chemical_list: D005465:Fluorocarbon Polymers; D010087:Oxides; C521561:lobetyolin; D053279:Polyynes; C040402:perfluorosulfonic acid; D006108:Graphite; D052203:Ferrosoferric Oxide
keywords: Differential pulse voltammetry; Electrochemical sensor; Lobetyolin; Magnetic functionalized reduced graphene oxide