Direct quantitative analysis from the current curve data of pulse voltammetric techniques

Pulse technologies have been widely employed in analytical electrochemistry systems. Double layer charging current has been an obstacle to the accurate measurement of faradaic current despite the theoretical and experimental efforts. Conventional pulse approaches record the current at a later pulse time for minimizing the capacitative effects and reducing the background currents. In this study, a method for extracting the quantitative information directly from the current curve data of pulse voltammetry is developed using trilinear decomposition algorithm. Feasibility of the proposed method is proved and an application study is performed for quantitative analysis of bovine serum albumin (BSA). The method can simultaneously obtain net faradaic current and double layer charging current directly from the measured signals, and the quantitative information can be obtained as well. Thus the performance of voltammetric techniques can be improved. Because the net signals are used, the sensitivities are increased by about 160%, 90% and 25% for normal pulse voltammetry, differential pulse voltammetry and staircase voltammetry, respectively. Quantitative determination of BSA in solutions was carried out with a calibration model of six samples. The recoveries are in a range from 98.1% to 102.9%, which may prove the reliability of the proposed method.