Design and Optimization of a New Voltammetric Method for Determination of Isoniazid by Using PEDOT Modified Gold Electrode in Pharmaceuticals

Fatma Demirkaya-Miloglu, Buket Ozdurak, Elmas Miloglu
2016 of Medical Sciences and Health Services Iranian Journal of Pharmaceutical Research   unpublished
Isoniazid (INH) was studied with regard to its electrochemical treatment on a strongly alkaline solution of a poly (3,4-ethylenedioxythiophene)-modified gold electrode, using both cyclic voltammetric and controlled potential techniques. Electrocatalytic performance measurements of this composite electrode toward oxidation of INH exhibited an increase of 4-folds in oxidation peak densities compared to the bare gold electrode. Central composite design method was used to obtain optimum
more » ... optimum experimental conditions, and used critical parameters (pH (A), scan rate (mV/s, B) and temperature (°C, C) to assess the effects on amperometric response. Optimum experimental conditions were achieved by using a pH of 9.2 with a scan rate of 260 mV/s and a temperature of 30 °C. Under these circumstances, a good linear relationship was observed between peak current densities and INH concentration in the range of 0.05-2 μM, with correlation coefficient of 0.9998. Furthermore, the method was very sensitive (limit of quantitation, 0.0043 μM), accurate (relative error,-5.65 to 4.03) and precise (relative standard deviation %, ≤ 7.97). The method was also applied to determine INH in pharmaceutical formulations, and statistically compared the results with the official method using the two one-sided equivalence test; the results were in good agreement with those obtained by the official and reported methods.