An innovative aluminium foil electrode modified with Al nanoparticles and EDTA for lead detection in biological samples.

This study presents a novel Aluminium foil-based electrode characterized by its affordability, flexibility, and ease of modification with carboxylic moiety-containing organic molecules. Upon foil modification with Aluminium nanoparticles and EDTA (AlNP-EDTA/AlE), the modified electrode exhibits remarkable activity in the oxidation of lead at potentials around -0.4 V. The lead signal is derived from the oxidation of lead deposited on the electrode surface using anodic stripping voltammetry (ASV). The addition of EDTA to AlNP/AlE increased the anodic peak current of lead by more than 500 %. The surface characterization of the electrode was performed by scanning electron microscopy (SEM) and infrared spectroscopy (IR), while its electroactive properties were evaluated by cyclic voltammetry (CV) and electrical impedance spectroscopy (EIS). Optimal operating parameters include pH 2.1, square-wave voltammetry (SWV) with an accumulation time of 60 s and an accumulation potential of -0.8 V. A low detection limit of 0.20 µmol/L and a relative standard deviation (RSD) of 3.0 % were achieved using five different electrodes. The effectiveness of AlNP-EDTA/AlE was further demonstrated with consistent results in biological samples spiked with Pb.

Síntesis de tioureas con isoniacida y niacida estructural: test frente a bacterias Gram + y Gram -

Se sintetizaron los compuestos N-(2-ni-cotinoilhidrazina-1-carbonotioil)benzamida (H3L1) y su isómero N-(2-isonicoti-noilhidrazina-1-carbonotioil)benzamida (H3L2) tipo N, S, O dadores, por reacción del isotiocianato de benzoilo con la hidracida nicotínica y la isoniacida, respectivamente. Los compuestos H3L1 y H3L2 fueron caracterizados por 1H-RM-N,13C-RMN, FT-IR y análisis elemental. Se realizó el análisis computacional utilizando las funciones de Fukui para determinar las razones por las cuales no se formaron los 1,2,4-triazoles. Se hicieron pruebas preliminares de los compuestos sintetizados frente a Staphylococcus aureus (Gram+) y Escherichia coli (Gram-). Se demostró importante actividad frente a las bacterias mencionadas.

The compounds N-(2-nicotinoylhydra-zine-1-carbonothioyl)benzamide (H3L1) and its isomer N-(2-isonicotinoylhydra-zine-1-carbonothioyl)benzamide (H3L2) type N, S, O donors, by reaction of benzoyl isothiocyanate with nicotinic hydrazide and isoniazid respectively were synthesized. The H3L1 and H3L2 compounds were characterized by 1H-NMR, 13C-NMR, FT-IR and elemental analysis. Computational analysis using the Fukui functions were performed to determine the reasons why the 1,2,4-triazoles were not formed. Preliminary tests of the synthesized compounds were carried out against Staphylo-coccus aureus (Gram+) and Escherichia coli (Gram-), having demonstrated significant activity against such bacteria.

Os compostos N-(2-nicotinoilhidrazina-1-carbonotioil)benzamida (H3L1) e seu isòmero N-(2-isonicotinoilhidrazina-1-carbonotioil)benzamida foram sintetizados. (H3L2) doadores tipo N, S, O, por reação de isotiocianato de benzoíla com hidrazida nicotínica e isoniazida, respectivamente. Os compostos H3L1 e H3L2 foram caracterizados por 1H-NMR, 13C-NMR, FT-IR e análise elementar. A análise computacional usando as funções de Fukui foi realizada para determinar as razões pelas quais os 1,2,4-triazóis não foram formados. Testes preliminares dos compostos sintetizados foram realizados contra Staphylococcus aureus (Gram+) e Escherichia coli (Gram-), tendo demonstrado atividade significativa contra as referidas bactérias.

Synthesis and characterization of silver(I) complex with mixed ligands saccharinate and 2-(2-pyridyl)bezimidazole / Síntesis y caracterización del complejo de plata(I) con ligandos mixtos sacarinato y 2-(2-piridil)bezimidazol / Síntese e caracterização do complexo de prata(I) com ligandos mistos sacarinato e 2-(2-piridil)benzimidazol

Abstract A new silver coordination compound [Ag(sac) (pbi)] was synthesized by reaction of silver(I) saccharinate with 2-(2-pyridyl)benzimidazole (pbi) in 64% yield. The characterization was performed by elemental analysis, IR, UV-Visible, XPS, 1H-NMR, and 13C-NMR spectroscopy. According to the results, silver is coordinating through three nitrogen atoms: one from saccharinate and the others from 2-(2-pyridyl) benzimidazole forming with this ligand a five-membered chelate ring.

Resumen Se sintetizó un nuevo compuesto de coordinación de plata, [Ag(sac)(pbi)], por reacción de sacarinato de plata(I) con 2-(2-piridil)bencimidazol (pbi) con un rendimiento de 64%. La caracterización se realizó por análisis elemental, espectroscopia IR, UV-Visible, XPS, 1H-RMN y 13C-RMN. De acuerdo con los resultados obtenidos la plata está coordinada a través de tres átomos de nitrógeno, uno del sacarinato y los dos restantes del 2-(2-piridil)-bencimidazol formando con este ligando un anillo quelato de cinco miembros.

Resumo O presente trabalho compreende a síntese de um novo composto de coordenação de prata, [Ag(sac)(pbi)], por reação de sacarinato de prata(I) com 2-(2-piridil)benzimidazol (pbi) com 64% de rendimento. A caracterização foi realizada por análise elementar, espectroscopia IV, UV-Visível, XPS, 1H-RMN e 13C-RMN. De acordo com os resultados obtidos, a prata é coordenada através de três átomos de nitrogênio, um do sacarinato e os outros dois do 2-(2-piridil)benzimidazol que formam com este ligando um anel de quelato de cinco membros.