Determination of Cadmium Using Retractable-pen-based Renewable Silver Amalgam Film Electrode

A novel and simple construction of retractable-pen-based renewable silver amalgam film electrode (RAE) was tested for the determination of Cadmium(II). RAE is based on a mechanical renewal of the amalgam film achieved by using mechanisms found in common retractable ballpoint pen. The minimum amount of liquid amalgam allowing several months of use, in addition to portability, long-term stability, simple renewal of the surface, and a wide cathodic potential window, make the RAE a suitable alternative to mercury and mercury film electrodes. Obtained limit of quantification (LOQ) for cadmium (II) was 54 nmol L-1 (6,1 ppb) in acetate buffer (pH 4.8).