Search

Novel methods were proposed for determining primaquine (PQN) in tablets by multiple-injection capillary zone electrophoresis (MI-CZE) and by short-end injection CZE (SEI-CZE), both with ultraviolet detection. The background electrolyte (BGE), consisting of 20 mmol/L of tris (hydroxymethyl) aminomethane and 30 mmol/L of hydrochloric acid at pH 2.0, was selected considering a comprehensive study involving the effective mobility versus pH curves of the analytes and BGE components. Experimental designs were applied in methods developments, showing the chemometric tool's applicability in achieving suitable electrophoretic conditions. A baseline resolution in the separation of adjacent peak pairs was obtained by injecting a spacer electrolyte for 18 s, with a voltage of + 15 kV, and the sample can be injected six consecutive times in a single run in less than 3 min, in the MI-CZE method. For the SEI-CZE method, the migration time of PQN was 0.6 min, and the method was applied to a demonstrative forced degradation study. Some validation parameters were evaluated for both methods, and all results were satisfactory, indicating that they can be implemented as PQN determination methods in routine quality control analyses., (© 2024 Wiley‐VCH GmbH.)

Mass spectrometry (MS) has found numerous applications in medicine and has been widely used in the detection and characterization of biomolecules associated with viral infections such as COVID-19. COVID-19 is a multisystem disease and, therefore, the need arises to carry out a careful and conclusive assessment of the pathophysiological parameters involved in the infection, to develop an effective therapeutic approach, assess the prognosis of the disease, and especially the early diagnosis of the infected population. Thus, the urgent need for highly accurate methods of diagnosis and prognosis of this infection presents new challenges for the development of laboratory medicine, whose methods require sensitivity, speed, and accuracy of the techniques for analyzing the biological markers involved in the infection. In this context, MS stands out as a robust analytical tool, with high sensitivity and selectivity, accuracy, low turnaround time, and versatility for the analysis of biological samples. However, it has not yet been adopted as a frontline clinical laboratory technique. Therefore, this review explores the potential and trends of current MS methods and their contribution to the development of new strategies to COVID-19 diagnosis and prognosis and how this tool can assist in the discovery of new therapeutic targets, in addition, to comment what could be the future of MS in medicine., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Malaria is a life-threatening disease being treated by oral medication. This is the best treatment to reduce morbidity and mortality, prevent disease progression to the most severe form, lower the transmission of the disease and hinder the appearance of strains resistant to antimalarials. According to the World Health Organization, the most common antimalarial drugs are chloroquine, primaquine, mefloquine, lumefantrine, artemether, and artesunate in single dosage forms or fixed-dose combination. Within this context, the present review aims to show the evolution of different analytical methods that have been applied to the determination of these antimalarial drugs in pharmaceutical formulations and human blood by liquid chromatography in the last 10 years, along with statistical analyses of the methods.

A novel method was proposed for simultaneous determination of artesunate (ATS) and mefloquine (MFQ) in fixed-dose combination tablets by capillary zone electrophoresis with simultaneous direct and indirect detection by ultraviolet (CZE-UV). The background electrolyte, consisting of 30/15 mmol L -1 TRIS/3,5-dinitrobenzoic acid buffer at pH 8.2, a chromophore buffer, was selected taking into account a detailed study involving the effective mobility vs. pH curves of the analytes and electrolyte compounds in association with the very low molar absorptivity of ATS. Suitable separation conditions, considering voltage, temperature and buffer concentration as factors, were achieved through the 3 3 Box-Behnken design investigation. The optimum baseline separation conditions were: injection pressure of 30 mbar for 10 s, cartridge temperature of 22.5 °C and positive voltage of +30 kV. The method proved to be rapid (5 minutes), simple, selective, linear (r 2 > 0.98), precise (relative standard deviation (RSD): ATS < 2.9% and MFQ < 2.2%) and accurate (recoveries: ATS 98.13-102.96% and MFQ 98.75-106.77%), proving to be suitable for routine quality control analysis.