A carbon paste electrode modified with poly

Poly(methylene disulfide) nanoparticles (PMDSNPs) were synthesized and characterized by FTIR, FESEM, EDX, and TGA. The nanomaterial was used to modify a carbon paste electrode to obtain a sensor for differential pulse anodic stripping voltammetric analysis of silver ion. The silver ions are accumulated on the modified electrode by reduction at a potential of -0.3 V. This is followed by the quantitation of adsorbed Ag(I) by differential pulse anodic stripping voltammetry. Under optimized conditions, the electrode has a dynamic range in the 3.0 x 10.sup.-12 to 1.0 x 10.sup.-9 mol L.sup.-1 Ag(I) concentration range, and the detection limit is 1.0 x 10.sup.-13 mol L.sup.-1. The relative standard deviation (for n = 6) is 1.8%, this showing good reproducibility. The method was successfully applied to the determination of Ag(I) in spiked tap and river waters and tea leaves. The results were in good agreement with those obtained by inductively coupled plasma optical emission spectrometry.