The use of a graphite-castor oil polyurethane composite electrode for the determination of hydroquinone in photographic developers

摘要

The performance of a new graphite-castor oil polyurethane composite electrode in the determination of hydroquinone in photographic developers in a differential pulse voltammetric (DPV)procedure is described.The 60% (graphite, w/w)composite electrode presented good stability, repeatability and accurate response.Limit of detection of 934nmolL~(-1)was observed for hydroquinone within a linear dynamic range from 66 to 530nmolL~(-1).The determination of hydroquinone in a photographic developer sample showed agreement with the label values in a 95% confidence level with maximum 2% relative error and recoveries between 100.1 and 100.4%.No need of sample preparation was required since the p-methylaminophenolsulfate (metol)present in the developer formulation did not interfered in the measurements.