ABSTRACT
The present study compared the performance of Ultra-high performance liquid chromatography (UHPLC) and UV-Vis spectrophotometry for the quantification of metformin hydrochloride in five commercially available metformin hydrochloride products with different strengths. The metformin hydrochloride was measured in the UHPLC with a mobile phase consisting of a mixture of 0.05 M phosphate buffer solution and methanol (35:65, v/v) with a pH of 3.6. Metformin hydrochloride was determined spectrophotometrically at 234 nm using a mixture of methanol and water as a blank. The methods' linearity for metformin hydrochloride was within the concentration range of (2.5-40 µg/ml) in both techniques. The validation process encompassed assessments of specificity, selectivity, linearity, accuracy, precision, the lower limit of quantification (LLOQ), the lower limit of detection (LLOD), robustness, and system suitability. For the UHPLC validation method, the repeatability and reproducibility (expressed as relative standard deviation) were less than 1.578 and 2.718 %, respectively. The LLOQ for metformin hydrochloride was 0.625 µg/ml, and the LLOD was 0.156 µg/ml. For the UV-Vis spectrophotometric validation method, the repeatability and reproducibility (stated as relative standard deviation) were less than 3.773 and 1.988 %, respectively. The percentage recovery results for the five brands of metformin hydrochloride tablets were (98-101 %) and (92-104 %) for the UHPLC and UV-Vis spectrophotometric methods, respectively. In conclusion, the described methodologies were successfully employed for the quantitative analysis of metformin hydrochloride in different pharmaceutical tablet products.
ABSTRACT
BACKGROUND: Previous studies have shown mortality benefits with corticosteroids in Coronavirus disease-19 (COVID-19). However, there is inconsistency regarding the use of methylprednisolone over dexamethasone in COVID-19, and this has not been extensively evaluated in patients with a history of asthma. This study aims to investigate and compare the effectiveness and safety of methylprednisolone and dexamethasone in critically ill patients with asthma and COVID-19. METHODS: The primary endpoint was the in-hospital mortality. Other endpoints include 30-day mortality, respiratory failure requiring mechanical ventilation (MV), acute kidney injury (AKI), acute liver injury, length of stay (LOS), ventilator-free days (VFDs), and hospital-acquired infections. Propensity score (PS) matching, and regression analyses were used. RESULTS: A total of one hundred-five patients were included. Thirty patients received methylprednisolone, whereas seventy-five patients received dexamethasone. After PS matching (1:1 ratio), patients who received methylprednisolone had higher but insignificant in-hospital mortality in both crude and logistic regression analysis, [(35.0% vs. 18.2%, P = 0.22) and (OR 2.31; CI: 0.56 - 9.59; P = 0.25), respectively]. There were no statistically significant differences in the 30-day mortality, respiratory failure requiring MV, AKI, acute liver injury, ICU LOS, hospital LOS, and hospital-acquired infections. CONCLUSIONS: Methylprednisolone in COVID-19 patients with asthma may lead to increased in-hospital mortality and shorter VFDs compared to dexamethasone; however, it failed to reach statistical significance. Therefore, it is necessary to interpret these data cautiously, and further large-scale randomized clinical trials are needed to establish more conclusive evidence and support these conclusions.
