RESUMO
Two rapid, smart and validated stability indicating HPLC and TLC techniques were developed to determine atenolol (ATE) and lercanidipine HCl (LER) simultaneously in their pharmaceutical formulation. HPLC chromatographic separation was implemented by using Microsorb C18 (250 × 4.6 mm, 5 µm) column, with mobile phase of acetonitrile and 20 mM potassium dihydrogen phosphate buffer pH 3.5 adjusted by orthophosphoric acid in the ratio of (65:35, v/v) at a flow rate of 1.2 mL/min at 240 nm also the injection volume adjusted to be 30 µL. These selected conditions effectively separated ATE and LER at a retention time of 2 and 6.7 min, respectively, by isocratic elution mode without any interference from the obtained degradation products of LER. The densitometric determination was performed by using precoated silica gel 60F254 aluminum plates and chloroform, methanol and triethylamine (11.3:1.3: 0.3, by volume) as a developing system. The detection wavelength for simultaneous estimation of both drugs was 240 nm in the presence of the oxidative product of LER. The RF values for ATE and LER were 0.22 and 0.78, respectively. The calibration curves of both techniques were constructed with linearity ranges of (5-55) µg.mL-1 and (1-55) µg.mL-1 for both ATE and LER, respectively, for HPLC determination. While for TLC, the linearity ranges were (1-4) µg/band and (0.2-1.4) µg/band for ATE and LER, respectively. LER degradation products were characterized using UPLC/MS and the suggested mechanisms and degradation pathways were introduced.
Assuntos
Atenolol , Di-Hidropiridinas , Cromatografia em Camada Fina/métodos , Reprodutibilidade dos Testes , Cromatografia Líquida de Alta Pressão/métodosRESUMO
An economical & eco-friendly spectrofluorometric method has been developed for the determination of prucalopride succinate (PRU) in human urine on the basis of the drug's native fluorescence. The type of solvent and the wavelengths of excitation and emission have been carefully selected for optimal experimental conditions. In deionized water, the fluorescence intensity was measured at λ emission 362 nm upon excitation at 310 nm. This bio-validated method was carried out using 30uL urine without any preliminary steps. The calibration curve for prucalopride succinate shows a linear relationship in a concentration range of 0.75-5.5 µg/mL. Accuracy and precision were obtained using 4 quality control samples which are: 0.75 µg/ mL (LLOQ), 2.25 µg/mL (QCL), 2.5 µg/mL (QCM) & 4.125 µg/mL (QCH). The validation of this proposed technique obeys European Medicines Agency (EMA) Guidelines for validating bioanalytical methods and the greenness assessment was evaluated according to the Analytical GAPI approach.
Assuntos
Benzofuranos , Humanos , Espectrometria de Fluorescência/métodos , Solventes , SuccinatosRESUMO
An effective electrochemical sensing platform for the simultaneous determination of benzocaine (BEN) and antipyrine (ANT) based upon titanium dioxide nanoparticle (TiO2)/graphene oxide nanosheet (GO) bulk modified carbon paste electrodes (TiO2-GO/CPE) is reported. The TiO2-GO/CPE electrochemical sensing platform is found to exhibit linear ranges from 1.0 × 10-6 to 1.0 × 10-4 M and 1.2 × 10-8 to 8.0 × 10-5 M for BEN and ANT, respectively. The TiO2-GO/CPE sensor is explored towards the analysis of BEN and ANT in oral fluid (saliva) and pharmaceutical products. The synergy between the graphene oxide nanosheets and titanium dioxide nanoparticles results in a dramatic enhancement in the sensitivity of the sensor through a combination of increased surface area and improved electron transfer kinetics compared to other electrode alternatives. The fabricated TiO2-GO/CPE exhibits high sensitivity and good stability towards the sensing of BEN and ANT and has the potential to be utilised as a clinical assay and QA in pharmaceutical products.
