Simultaneous determination of ranitidine and metronidazole at glassy carbon electrode modified with single wall carbon nanotubes

Single-walled carbon nanotubes(SWCNTs) were dispersed into DMSO, and a SWCNTs-film coated glassy carbon electrode was achieved via evaporating the solvent. The results indicated that CNT modified glassy carbon electrode exhibited efficiently electrocatalytic reduction for ranitidine and metronidazole with relatively high sensitivity, stability and life time. Under conditions of cyclic voltarnmetry, the potential for reduction of selected analytes is lowered by approximately 150 mV and current is enhanced significantly (7 times) in comparison to the bare glassy carbon electrode. The electrocatalytic behavior is further exploited as a sensitive detection scheme for these analytes determinations by hydrodynamic amperometry. Under optimized condition in amperometric method the concentration calibration range, detection limit and sensitivity were about, 0.1 -200 mu M, detection limit (S/N= 3) 6.3 x 10(-8) mol L-1 and sensitivity 40 nA/ mu M for metronidazole and 0.3 -270 mu M 7.73 x 10(-8) mol L-1 and 25 nA/mu M for ranitidine. In addition, the ability of the modified electrode for simultaneous determination of ranitidine and metronidazole was evaluated. The proposed method was successfully applied to ranitidine and metronidazole determination in tablets. The analytical performance of this sensor has been evaluated for detection of these analytes in serum as a real sample.