Abstracto

Determination of hydrochlorothiazide in pharmaceutical formulations using activated carbon paste electrode by cyclic voltammetry

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.