title: Highly sensitive voltammetric sensor based on immobilization of bisphosphoramidate-derivative and quantum dots onto multi-walled carbon nanotubes modified gold electrode for the electrocatalytic determination of olanzapine.
abstract: In the present paper, a new bisphosphoramidate derivative compound, 1, 4-bis(N-methyl)-benzene-bis(N-phenyl, N-benzoylphosphoramidate) (BMBPBP), was synthesized and used as a mediator for the electrocatalytic oxidation of olanzapine. The electro-oxidation of olanzapine at the surface of the BMBPBP/CdS-quantum dots/multi-walled carbon nanotubes (BMBPBP/CdS-QDs/MWCNTs) modified gold electrode was studied using cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. This sensor showed an excellent electrocatalytic oxidation activity toward olanzapine at less positive potential, pronounced current response, and good sensitivity. The diffusion coefficient and kinetic parameters (such as electron transfer coefficient and the heterogeneous rate constant) were determined for olanzapine oxidation, using the electrochemical approaches. Surface morphology and electrochemical properties of the prepared modified electrode were investigated by scanning electron microscopy (SEM), cyclic voltammetry and electrochemical impedance spectroscopy techniques. The hydrodynamic amperometry at rotating modified electrode at constant potential versus reference electrode was used for detection of olanzapine. Under optimized conditions, the calibration plot was linear in the concentration range of 20 nM to 100 μM and detection limit was found to be 6 nM. The proposed method was successfully applied to the determination of olanzapine in pharmaceuticals and human serum samples.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran.
authors.forename: Leila
authors.initials: L
authors.lastname: Mohammadi-Behzad
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran. Electronic address: mbgholivand@yahoo.com.
authors.forename: Mohammad Bagher
authors.initials: MB
authors.lastname: Gholivand
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Shamsipur
authors.affiliation: Department of Chemistry, Tarbiat Modares University, Tehran, Iran.
authors.forename: Khodayar
authors.initials: K
authors.lastname: Gholivand
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Barati
authors.affiliation: Department of Chemistry, Tarbiat Modares University, Tehran, Iran.
authors.forename: Akram
authors.initials: A
authors.lastname: Gholami
mesh_terms: D001569:Benzodiazepines / Q000737:chemistry*; D004566:Electrodes; D006046:Gold / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D037742:Nanotubes, Carbon / Q000737:chemistry*; D000077152:Olanzapine; D045663:Quantum Dots
chemical_list: D037742:Nanotubes, Carbon; D001569:Benzodiazepines; D006046:Gold; D000077152:Olanzapine
keywords: Bisphosphoramidate compounds; Carbon nanotubes; Olanzapine; Quantum dots; Scanning electron microscopy