Mechanism of Electro-Oxidation of Metamizole Using Ciclic Voltammetry at a Glassy Carbon Electrode

Abstract

Cyclic Voltammetry at glassy carbon electrode was applied to study the electro-oxidation of Metamizole, a pro-drug largely used in many countries as analgesic which the therapeutic properties are attributed to its hydrolyzed form. Metamizole presents three oxidation processes in aqueous (Britton Robinson Buffer) and DMF media. The first process was characterized as reversible in the last medium. The differentiation between the process associated with the Metamizole and its respective hydrolyzed form the MAA, was investigated and allowed the proposition of a mechanism for the Metamizole electro-oxidation.

The Analgesic Metamizol (Dipyrone). Part 2: Adsorption, Oxidative and Reductive Degradation

“…oxidises and forms an iminium radical cation. In the reversed scan, a small cathodic peak can be observed at 0.3 V. After Bacil et al [13,14], the oxidised metamizole can subsequently react (dimerize) at 0.5 V (EC mechanism). The oxidation process at 0.9 V is common to all antipyrines.…”

The Analgesic Metamizole (Dipyrone) and Its Related Products Antipyrine, 4-Aminoantipyrine and 4-Methylaminoantipyrine. Part 1: Mass Spectrometric and Electrochemical Detection

“…Several electrochemical investigations of metamizole have been carried out with different types of electrodes, including glassy carbon electrodes [20] and carbon paste electrodes [21]. Metal electrodes as platinum were used by Basaez et al [22] while Munoz [23] used gold electrodes.…”

“…Metamizole (dipyrone or Novalgin ® ) is a non-opioid analgesic with a high potential. The analgesic effect is attributed to the inhibition of cyclooxygenase (COX) and the disabling of prostaglandin synthesis [6]. Because metamizole can cause an allergic response and rhinoconjunctivitis (a disease of the nasal mucosa), as well as agranulocytosis (a reduction of granulocytes) [6], metamizole has been withdrawn from the market in some countries.…”

“…The analgesic effect is attributed to the inhibition of cyclooxygenase (COX) and the disabling of prostaglandin synthesis [6]. Because metamizole can cause an allergic response and rhinoconjunctivitis (a disease of the nasal mucosa), as well as agranulocytosis (a reduction of granulocytes) [6], metamizole has been withdrawn from the market in some countries. However, metamizole is still widely available and used in countries such as Germany, Spain and France [2].…”

Desenvolvimento de eletrodos compósitos de carbono e poliestireno para aplicações eletroanalíticas

“…A literatura descreve a utilização de eletrodos à base de carbono para analises de um grande número de compostos químicos [103][104][105][106][107][108][109][110][111][112][113]. Os eletrodos compósitos desenvolvidos neste estudo foram utilizados para a avaliação da resposta voltamétrica de diversos compostos, dentre os quais: cisteína, ácido ascórbico, ácido gálico, peróxido de hidrogênio, nitrito, riboflavina, dipirona e paracetamol, cujos CVs estão apresentados na…”