| Abstract: | The work demonstrates a simple method for sensitive detection of Ca2+ ion by electrochemical response of alizarin red S (ARS) and Ca-ARS at a gold nanoparticle modified glassy carbon electrode (GCE). In the 0.1 M KOH, a sensitive reduction peak was observed at ?0.795 V at the gold nanoparticles modified electrode. The peak currents were proportional to the concentrations of Ca2+ ion in the range of 2.0 × 10?7 M–1.2 × 10?4 M. For the different pulse voltammetry (DPV) methods, the detection limit was 2.57 × 10?8 M. The reaction mechanism was primarily determined by cyclic voltammetry, and the experimental results showed that the electrode processes were quasireversible responses of ARS and irreversible responses of ARS-Ca. In addition, the method was simple, fast, precise, and was used in the determination of calcium in blood serum with satisfactory results. |
