Here, we developed a simple and sensitive electroanalytical methodology and quantified aliskiren pharmaceutical formulations, as well as human serum samples by square-wave voltammetry. The analytical signal response was obtained by electrochemical oxidation of the aliskiren drug at a boron-doped diamond (BDD) electrode. The determination was carried out in 0.04 M Britton-Robinson pH 8 buffer solution. Aliskiren oxidation reveals well-defined irreversible oxidation peak. The analytical curve was obtained in the concentration range from 1.81 × 10 -5 to 1.63 × 10 -4 M (r = 0.997). Limits of detection and of quantification for aliskiren were 2.5 × 10 -8 and 8.4 × 10 -8 M, respectively. Recovery values were in the range 98.2-100.2 %, indicating no matrix interference effects on the analytical determination of aliskiren in commercial samples. The presence of physiologically common interferents contained in human serum negligibly affects the electroanalytical response of aliskiren that after standardsolution additions yielding good average recoveries 95.5 to 97.8 %. The BDD electrode exhibited a stable, selective and sensitive response to aliskiren in the presence of interferents.Aliskiren recoveries values ranged from 95.5% to 97.8% in presence of serum demonstrate the elevated efficiency of the methodology. The BDD electrode shows a stable and reproducible response without any influence of interferents commonly existing in human blood. The results obtained are shown in Table 3. Table 3 CONCLUSION In this investigation, aliskiren displayed one oxidation peak when cyclic and square-wave voltammetry experiments were conducted using BDD electrodes. Based on these experiments, an electroanalytical methodology for the determination of aliskiren in water and commercial pharmaceutical products was developed. The electrochemical responses of pharmaceutical formulations were identical to those of standard aliskiren and no influence of others agents contained in commercial products on the voltammetric responses was observed. Aliskiren recovery values ranged from 98.2 to 100.2 % demonstrated the elevated efficiency of the developed methodology. Consequently, given it's easily of use, high sensitivity, and low analysis time, the proposed methodology can be successfully used to determine trace aliskiren in several commercial products. Recovery experiments carried out to evaluate matrix effects (serum) after standard-solution additions yielding good average recoveries 95.5 to 97.8 % for aliskiren indicating that there were no important matrix interferences for the samples analyzed by the proposed method.
RESUMO Este trabalho investigou o processo de hidrólise química de poli(tereftalato de etileno) (PET) em meio alcalino; especificamente de garrafas incolores e coloridas pós-uso. A reciclagem química de embalagens PET pós-uso ainda é muito pouco explorada no Brasil, não sendo tão diferente do que está sendo praticado em outros países. Dentre variáveis possíveis de investigação, aquelas estudadas neste trabalho foram a concentração de hidróxido de sódio (NaOH) e a cor do PET. A reação de despolimerização do PET pós-uso foi realizada na concentração de 1,0, 3,0, 5,0, 7,5 e 10,0 mol L-1 de NaOH, sendo que em 7,5 mol L-1 foi aquela que mostrou os melhores resultados, relativamente à extensão da reação e à pureza do monômero recuperado, o ácido tereftálico (TPA). A reação também foi feita para PET de cores diferentes, na concentração de 7,5 mol L-1 de NaOH, cujos resultados mostraram um menor desempenho quando comparados com aqueles obtidos para o PET não colorido. Esse resultado sugere ser devido à presença de corantes, que pela estrutura química dos mesmos, competem pelo ataque nucleofílico do íon hidroxila (OH-), durante a reação de hidrólise do PET. As análises por Espectrofotometria no Infravermelho (FTIR), Difração de Raios X (DRX) e Termogravimétrica (TGA/DTG) confirmaram que os produtos de reação resultaram em TPA, uma vez que os espectros foram coincidentes com aqueles do TPA comercial. O crescente consumo de embalagens PET e o descarte ambiental aleatório precisam de soluções rápidas; os resultados do presente trabalho são importantes e corroboram com o avanço da pesquisa para a reutilização de matéria prima.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.