Authors:Maha F. Abdel-Ghany, Omar Abdel-Aziz, Miriam F. Ayad and Mariam M. Tadros
New, simple, selective, and sensitive liquid chromatography–ultraviolet (LC–UV) methods have been developed and subsequently validated for simultaneous determination of linagliptin–empagliflozin combination and simultaneous determination of alogliptin benzoate–pioglitazone hydrochloride combination. Linearity was found to be acceptable over the concentration ranges of 2–50 μg mL−1, 4–100 μg mL−1, 0.5–25 μg mL−1, and 1–25 μg mL−1 for linagliptin (LNG), empagliflozin (EMG), alogliptin (ALG), and pioglitazone (PGN), respectively. All the methods were applied successfully to the analysis of the pharmaceutical dosage forms. The optimized methods were validated and proved to be robust and accurate for the quality control of the mentioned drugs in their different pharmaceutical dosage forms.
Authors:Lobna A. Hussein, Maha F. Abdel Ghany and Hend Z. Yamani
An efficient and fast microwave-assisted extraction (MAE) technique was developed for extracting trigonelline as an indicative biomarker for the quality control of Trigonella foenum-graecum seeds. The MAE procedure was optimized and compared with other conventional extraction techniques. The optimal conditions of MAE were 50% methanol as solvent, solid—liquid ratio 1:20 g mL−1, irradiation power 40%, and two extraction cycles, 3 min each. The proposed extraction technique produced a maximum yield of 7.89 mg g−1 trigonelline in 6 min which was 1.28 and 2.20 times more efficient than 3 h of heat reflux and 15 h of maceration extraction, respectively. Furthermore, rapid high-performance thin-layer chromatographic and high-performance liquid chromatographic methods for the quantification of trigonelline were established and validated. The methods were found to be simple, sensitive, precise, accurate, and specific for the estimation of trigonelline in T. foenum-graecum seeds extract and overcame disadvantages of previously published methods.