Screen-printed Prussian Blue modified electrode for simultaneous detection of hydroquinone and catechol

Abstract

A simply and high selectively electrochemical method for simultaneous determination of hydroquinone (HQ) and catechol (CC) has been developed at an electrochemically activated screen-printed carbon electrode (SPCE) modified with Prussian Blue (PB). The PB acted as a mediator and thereby enhanced the rate of electron transfer in chemical reaction. Various optimization studies such as the pH of the measuring solution, linear range of response, sensitivity and detection limit, were conducted to obtain maximum amperometric responses for analytes measurement. Differential pulse voltammetry (DPV) was used for the simultaneous determination of HQ and CC in their mixture, and the peak-to-peak separation for HQ and CC was about 0.11V. The two corresponding well-defined oxidation peaks of HQ and CC at activated Prussian Blue-modified screen-printed carbon electrode (PB-SPCE) occur at −0.012V and +0.094V, respectively. Under the optimized condition in DPV, the oxidation peak current of HQ and of CC is linear over a range from 4.0×10−6M to 9.0×10−5M HQ and from 1.0×10−6M to 9.0×10−5M CC. The obtained detection limit for HQ and CC was 1.17×10−7M and 4.28×10−7M, respectively. DPV can be used for individual or simultaneous determination of HQ and CC. The proposed activated PB-SPCE was successfully applied to the simultaneous determination of HQ and CC in spiked tap water. Using the standard addition method, the average recovery of the proposed method based on activated PB-SPCE was 99.03% and 95.87% for HQ and CC, respectively.