title: Sub-second adsorptive fast Fourier transform coulometric technique as a novel method for the determination of nanomolar concentrations of sodium valproate in its pharmaceutical preparation in flowing solution systems.
abstract: In this work, a novel electrochemical technique has been developed for determination of nanomolar concentration of sodium valproate in flow-injection systems. The detection was done by adsorptive fast Fourier transform coulometric (AFFTC), in which the potential waveform consists of potential steps for cleaning, accumulation, and a potential ramp that was continuously applied on an Au disk microelectrode. Moreover, a special computer program is introduced based on numerical method, for calculation of the analyte signal (which is the partial and total charge exchanges at the electrode surface) and noise reduction. The optimum parameters were: pH value of 2.0, scan rate value of 40 Vs(-1), accumulation potential of 200 mV and accumulation time of 0.3 s. Detection limit of the method for sodium valproate was 9.0x10(-9) M. The relative standard deviation of the method at 1.3x10(-7) M was 2.0% for 10 runs.
authors.affiliation: Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran, Iran. Norouzi@khayam.ut.ac.ir
authors.forename: Parviz
authors.initials: P
authors.lastname: Norouzi
authors.forename: Simindokht
authors.initials: S
authors.lastname: Shirvani-Arani
authors.forename: Parandis
authors.initials: P
authors.lastname: Daneshgar
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Ganjali
mesh_terms: D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods*; D005583:Fourier Analysis; D008832:Microchemistry / Q000295:instrumentation / Q000379:methods*; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D004364:Pharmaceutical Preparations / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014635:Valproic Acid / Q000032:analysis*
chemical_list: D004364:Pharmaceutical Preparations; D014635:Valproic Acid