Modified Forms of Differential Pulse Polarography for Improved Sensitivity When Kinetically Controlled Processes Overlap

Conventional differential pulse and square wave polarographic methods are completely inadequate for the determination of 2-acetamldoacryllc acid (N -acetyIdehydroaianlne). The negative potential required for reduction of the compound, combined with the need for highly acidic conditions, Introduces a resolution problem that limits the detection to concentrations above 10~₃M. A detailed investigation of alternative differential pulse poiarographic modes shows that a 3 orders of magnitude improvement in the limit of detection can be achieved by use of the technique called differential pulse reversible polarography. This technique exploits the different time dependencies of the kinetically controlled reductive process for 2-acetamidoacrylic acid to that for the interfering hydrogen ion reduction wave to minimize the influence of the latter on the measured response. This substantial Improvement in detection limit is required for the development of a technique for the monitoring of wool degradation.