Development of Simple HPLC-UV Method for the Simultaneous Determination of Repaglinide, Dexamethasone, and Remdesivir, and its Application to Synthetic Mixture and Human Plasma

Background: The onset of the COVID-19 pandemic caused numerous difficulties in the treatment of cardiovascular diseases and diabetes mellitus. A persistent risk of developing severe complications and increased mortality from the COVID-19 infection has been reported. In the clinical studies, patients receiving remdesivir and dexamethasone as COVID-19 combination therapy simultaneously with some type II diabetes therapeutic regimens had been reported to have a considerably better state and recover faster. Unfortunately, there is not enough information on the combination of meglitinides, remdesivir, and dexamethasone, and therefore, careful monitoring of the patients' everyday health condition is needed.Objectives: The present study aimed to describe a high-performance liquid chromatographic method for the determination of repaglinide, dexamethasone, and remdesivir in laboratoryprepared mixtures and human plasma by UV detection.Methods: Isocratic elution of the mobile phase (consisting of 0.1% trifluoroacetic acid in water and acetonitrile in the ratio 70:30 v/v) was set at a flow rate of 1.0 ml/min, and the developed analytical procedure has been found to be fast and simple. Chromatographic determination was performed on a Purospher (R) RP - 18 column at room temperature and a UV detector was set at 235 nm.Results: The developed method was validated for linearity in the range 2-32 mu g/ml. Calibration curves were linear over the selected range with correlation coefficients (R-2) greater than 0.996. The coefficients of variation for intraday and interday assay were < 2% and the recovery percentages from plasma ranged from 93.83 to 106.49%.Conclusion: The developed effective and specific method can be applied in routine quality control and clinical laboratory practice.