[en] An alizarin-modified electrode for the voltammetric determination of aluminium(III) is reported. The single-use modified electrode is simply prepared by dip-coating a high-density graphite electrode in an N,N-dimethylformamide solution of alizarin. Optimum experimental conditions for aluminium(III) determination include a solution pH of 8.4±0.2, an accumulation time of 1 min and use of the differential-pulse mode for measurement of the oxidation peak of the aluminium(III)-alizarin complex. The detection limit is 1.5x10^-7 M, the response is linear up to 1.0x10^-5 M and the relative standard deviation for replicate preparations of the electrode [at 7.5x10^-6 M Al(III)] is 3.8%. The determination of aluminium in soil samples is reported. (author). 14 refs.; 5 figs.; 2 tabs

[en] Eleven chelating tetrazole-containing ligands have been synthesized, and their complexes with palladium (II) and ruthenium (II) prepared. Proton n.m.r. spectroscopy, electronic absorption spectroscopy and cyclic voltametry have been used to study the nature of the metal-ligand interactions in these complexes. The negatively charged tetrazolate group is shown to be a strong electron donor with very different properties to those of the protonated or alkylated tetrazole group. This leads to pH control of the properties of transition metal complexes containing such ligands. 13 refs., 2 tabs., 3 figs.,ill