Validation of a chromatographic method for the assessment of sodium metamizole in Dipyrone-600 and Spasmoforte

Abstract

Dipyrone-600 (injectable), is a pharmaceutical formulation with analgesic and non-steroidal anti-inflammatory action (NSAID) of a chemical compound derived from pyrazolone, Metamizole sodium, an inhibitor of prostaglandin synthesis. Due to the emergence and spread of the COVID-19 disease in Cuba and the cessation of the importation of this drug from China, it was necessary to carry out its production in Cuba (UEB AICA+), for the palliative treatment of fever and pain in patients with COVID-19 and other conditions. The valuation of Sodium Metamizole (as an active pharmaceutical ingredient) in Dipirona-600 and Espasmoforte is carried out by iodometry, a volumetric method that requires controlled conditions, because different factors can affect its accuracy; Furthermore, Dipyrone is photosensitive and oxidizes easily. Due to this, the Physico-chemical Quality Control Laboratory needs to have a simple, fast and specific method to guarantee the quality of the injectable and to carry out stability studies. An isocratic method in reversed phase was validated by high performance liquid chromatography (HPLC) with UV detection for the valuation of Metamizole Sodium in Dipyrone-600 with a view to its introduction in the mentioned Laboratory. The validation parameters evaluated were: Specificity, Linearity, Accuracy and Precision (Repeatability and Intermediate Precision). For the assessment of Metamizole sodium in Esparmoforte (injection), only specificity and linearity were assessed. The chromatographic method for the valuation of sodium Metamizole met the acceptance criteria for each validation or performance parameter evaluated and was used in the analysis of several batches of Dipirona-600 and one batch of Espasmoforte