Optimization of a spectrofluorimetric method based on a central composite design for the determination of potassium losartan in pharmaceutical products

Abstract

Here, a spectrofluorimetric method for the determination of potassium losartan (PL) in pharmaceutical products is described. The effects of critical parameters, pH, acid molarity, and temperature, on the fluorescence intensity of PL were analyzed, and these parameters were optimized using a central composite design (CCD). The highest fluorescent intensity at excitation (λex) and emission (λem) wavelengths of 248 nm and 410 nm, respectively, was achieved using 0.01 M sulfurous acid (pH 2) at 21.6 °C. Under optimum conditions, the method was linear from 0.025-0.5 µg/mL, with a reasonably high correlation coefficient (0.9993). Furthermore, the method was very sensitive (LOQ, 0.006), accurate (RE, ≤7.06), and precise (%RSD, ≤6.51). After development and validation of the method, samples containing PL were analyzed with this method, and the obtained data were statistically compared with those obtained with a previously published reference method using a two one-sided equivalence test (TOST). According to the data, the results from the proposed and reference assays were equivalent. Descreve-se método espectrofluorométrico para a determinação de losartana potássica (PL) em produtos farmacêuticos. Os efeitos de parâmetros críticos (pH, molaridade ácida e temperatura) na intensidade da fluorecência foram otimizados usando o planejamento de componente central (DCC). A mais alta intensidade fluorescente com λex=248 nm e λem= 410 nm foi obtida usando ácido sulfúrico 0.01 M (pH 2) e 21.6 ºC. Nas condições ideais, a linearidade do método foi estabelecida na faixa de concentração de 0.025-0.5 µg/mL com coeficiente de correlação bastante elevado (0.9993). Além disso, o método foi muito sensível com valor de LOQ 0.006, exato (RE≤7.06) e preciso (RSD%≤6.51). Depois do desenvolvimento e validação do método, amostras de medicamentos contendo PL foram analisadas com este método e os resultados obtidos foram comparados estatisticamente com método de referência, publicado anteriormente, usando o Teste de equivalência TOST (Teste de Equivalência Unilateral). De acordo com os dados estatísticos, os resultados do ensaio de referência e do método proposto foram equivalentes.Uniterms: Losartana potássica/planejamento de componente central. Espectrofluorimetria/análise quantitativa. Formulações farmacêuticas/análise quantitativa.

Autofluorescence excitation‐emission matrices as a quantitative tool for the assessment of meat quality

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Behaviour of the faujasite zeolite occluded with Ti(IV) and Zr(IV) and its interaction with Nickel Hexacyanoferrate (III) : A comparative study in the voltammetric detection of isoniazid

“…Thus, IZN determinations in biological fuids are extremely important for therapeutic control, requiring quick, sensitive and selective quantitative IZN determination methods in biological fuids [16,17]. In this regard, several analytical methods have been developed for IZN quanti cation in biological samples, including high performance liquid chromatography [18], capillary electrophoresis [19], fuorimetry [20], chemiluminescence [21], titration [22], spectrophotometry [23] and voltammetric methods [24].…”