Determination of hydrochlorothiazide in pharmaceutical formulations using activated carbon paste electrode by cyclic voltammetryAuthor(s): S.S.Badawy, B.AbdelAzeem
Avoltammetric study of hydrochlorothiazide (HTZ) at activated carbon paste electrodewas carried out. The drug in phosphate buffer (0.2mol/l, pH7.7) is oxidized at +800mVusing 100mVs-1 scanning rate, giving rise to a well-defined anodic peak. Cyclic voltammetric studyindicates that the oxidation process is irreversible and diffusion-controlled.Asensitive, simpleandtime-savinganodiccyclicvoltammetric procedure hasbeen developed.The procedure has been applied for the drug determination in pure formand in commercial tablets with no prior extraction. HTZ chemiluminesshowed a significant current response at activated carbon paste electrode under the optimumconditionswith two lineardynamicranges (experimentaldetectionlimit of the standard solutionwas 2×10-6mol/l). The linear calibration rangeswere between 6.5×10-6 - 1×10-4mol/ l and 1×10-4 - 3×10-3mol/l HTZ.