A Silsesquioxane Organically Modified with 4‐Amino‐5‐(4‐pyridyl)‐4H‐1,2,4‐triazole‐3‐thiol: Thermal Behavior and Its Electrochemical Detection of Sulfhydryl Compounds

Abstract

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.

Isoniazid‐sensing Behavior of a Hybrid Silsesquioxane and Cobalt Pentacyanonitrosylferrate‐based Nanocomposite

“…In this context, silsesquioxanes can be applied in diverse technological areas, such as additives [10], glass and ceramic matrices precursors [11,12], dendrimer precursors [13][14][15][16], polymers [17,18], fluorescent polymeric materials [19,20]; liquid crystal precursors [21,22], organic-inorganic hybrid material precursors [23][24][25][26], silica interface precursors [27,28], in electroactive films [29]; as adsorbents [30][31][32], homogeneous and heterogeneous catalysts [33,34] and antibacterials and biocides [35]. They are also applied in thin films and coatings, aiming at several applications, including nanocomposites [36][37][38].…”

Silsesquioxane organofunctionalized with 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole: Preparation and subsequent reaction with silver and potassium hexacyanoferrate(III) for detection of l-cysteine

“…Thus, the chemistry of organofunctionalized silsesquioxanes has emerged as a fascinating new field of modern nanotechnology [28,29]. Some studies were recently published by the Do Carmo research group on the role of chemically modified silsesquioxanes, which act as electron mediators or electrochemical sensors [30][31][32][33][34].…”

Reactivity of a Silsesquioxane Organofunctionalized with 4-Amino-5-Phenyl-4H-[1,2,4]-Triazole-3-thiol: Complementary Characterization and an Application to Chronoamperometric Detection of L-Dopamine

“…Through this process the functionalized octakis(3chloropropyl)octasilsesquioxane have some properties enhanced, such as improved thermal and mechanical resistance, without affecting its characteristics [8,[20][21][22], and also increased adsorption capacity of metal ions in solution [23][24][25][26][27][28][29], thus the use of this procedure can generate types of octakis(3-chloropropyl)octasilsesquioxanes (chloropropyl-T8) with different properties and applications. They are also used as catalysts [7,28], dendritic precursors [7,29], polymer precursors [30], biocompatible materials, and as precursors for developing liquid crystals [31], homogeneous and heterogeneous catalysis [28,32], electroactive films [33], additives [34,35], antibacterials and biocides [36], and are also used in thin films and coatings for various applications, including nanocomposites [37][38][39][40].…”