Abstract
For the first time, an electrochemical method was proposed for the simultaneous determination of isoniazid (INZ), pyrazinamide (PYZ) and buspirone HCl (BPH) at graphene oxide (GO)/poly-l-arginine (PAG)-modified glassy carbon electrode (GCE). The GO was synthesized by modified Hummer's method and the surface morphologies of GO and PAG were characterized by scanning electron microscopy (SEM). The simultaneous determinations of INZ, PYZ and BPH were determined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The proposed GO/PAG/GCE sensor has a wide linear range of 20 to 1,400 mu M for INZ, 25 to 900 mu M for BPH and 25 to 1,600 mu M for PYZ, respectively. The low limit of detection (LOD) values was found as 2.59, 3.54 and 3.28 mu M respectively, for INZ, BPH and PYZ. The practicality and applicability of the proposed electrode was demonstrated in blood serum and commercially available pharmaceutical tablets. In addition, the obtained results for pharmaceutical tablets were in good agreement with the label claim of the tablets and the proposed method could be employed in pharmaceutical laboratories in the near future.