Title:Voltammetric Analysis of Ephedrine in Pharmaceutical Dosage Forms and Urine Using poly(Nile Blue A) Modified Glassy Carbon Electrode
VOLUME: 24 ISSUE: 3
Author(s):Fatma Ağın, Gökçe Öztürk and Dilek Kul*
Affiliation:Department of Analytical Chemistry, Faculty of Pharmacy, Karadeniz Technical University, Ortahisar, 61080, Trabzon, Department of Analytical Chemistry, Faculty of Pharmacy, Karadeniz Technical University, Ortahisar, 61080, Trabzon, Department of Analytical Chemistry, Faculty of Pharmacy, Karadeniz Technical University, Ortahisar, 61080, Trabzon
Keywords:Ephedrine, poly(Nile blue A), voltammetry, modified glassy carbon electrode, electropolymerization,
pharmaceuticals.
Abstract:
Objective: The electrochemical analysis of ephedrine which is a sympathometric drug
has been studied using poly(Nile blue A) modified glassy carbon electrodes, cyclic voltammetry,
differential pulse voltammetry and square wave voltammetry.
Methods: The modified electrodes were prepared by potential cycling electropolymerization of
Nile blue A in 0.1 M phosphate buffer solution at pH 6.0. The redox behavior of ephedrine was
investigated in different buffer solutions at pH values between 5.5 and 9.0.
Results: Scan rate studies showed that the electron transfer reaction of ephedrine was diffusion
controlled. A linear response was obtained between the peak current and the ephedrine
concentration in the range of 0.6 to 100 μM with a limit of detection of 2.91×10-3 μM for
differential pulse voltammetry in Britton-Robinson buffer solution at pH 9.0. The linearity range of
ephedrine in human urine was between 1.0 and 100 μM with a detection limit of 8.16 nM.
Conclusion: The recovery studies in both pharmaceutical dosage forms and urine showed that the
proposed method ensured good selectivity, precision and accuracy without any interference from
inactive excipients.
