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This paper describes the preparation of a nanostructured silsesquioxane, the cloropropilsilsesquioxano (S) that was organofunctionalised with the 4-amino-5-4(pyridyl)-4H-1,2,4-triazole-3-thiol (APTT), the material obtained of the functionalization was described as SA. The material SA was characterized by spectroscopy in the region of infrared (FTIR). After proper characterization, were carried studies on adsorption of metallic ions such as Cu 2+ , Ni 2+ and Cd 2+ in the active sites of SA. Different methods were studied in the adsorption of metal ions above: aqueous, ethanol 42% and ethanol 99%, determining the adsorption equilibrium time, which for both means and metals the maximum time averaged 35 minutes. After determining the adsorption equilibrium time of metal ions in each system, we determined the specific sorption capacity (Nf max ) through adsorption isotherms. The results suggest that the sorption of metal ions on DPPIPS occurs mainly by surface complexation and a Langmuir model allowed describing the sorption of the metal ions on SA. The excellent adsorptive capacity made possible the development of a method for determination of metal ions at trace level in real samples such as waste water, ethanol fuel and alcoholics beverages.

The octakis(3-chloropropyl)silsesquioxane (SS) was organofunctionalized with 4-amino-5-4(pyridyl)-4H-1,2,4-triazole-3-thiol. The product formed (SA) was undergo another reactions in two steps, first with copper and so hexacyanoferrate (III) to form CuHSA. The organofunctionalized silsesquioxane was characterized by the following techniques: scanning electron microscopy (SEM), Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) in solid state, and thermogravimetric analysis in air and nitrogen atmosphere. The composite CuHSA was incorporated into a graphite paste electrode and the electrochemical behavior studies were conducted with cyclic voltammetry. The cyclic voltammogram of the modified graphite paste electrode with CuHSA showed one redox couple with formal potentialEθ′=0.75 V versus Ag/AgCl(sat)(KCl 1.0 mol L−1;v= 20 mV s−1) attributed to the redox process Fe(II)(CN)6/Fe(III)(CN)6of the binuclear complex formed. The redox couple presents an electrocatalytic response of sulfhydryl compounds such as n-acetylcysteine and l-cysteine. For determination of n-acetylcysteine and l-cysteine the modified graphite paste electrode showed a linear region in the concentration range of 2 to 20 mmol L−1. The modified electrode was chemically and electrochemically stable and showed good reproducibility.

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