Evaluating quackery formulations: LC-MS/MS based method for detecting glucocorticoid content

Abstract

Glucocorticoids are widely used as highly effective drugs for treating inflammatory diseases. In this study, a method was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to simultaneously determine four glucocorticoids, including betamethasone, dexamethasone, hydrocortisone, and prednisolone in unauthorized or unregulated medicinal powders often associated with quackery formulations. Commercially available standards were used for method development and glucocorticoid detection. Glucocorticoids were extracted from the samples with methanol, which were then chromatographically separated using two mobile phases (0.1 % formic acid in water and 0.1 % formic acid in acetonitrile) in an isocratic flow on an Agilent Poroshel 120 C18 column (2.1 mm x 75 mm x 2.7 m). The validated analytical measuring range (AMR) of betamethasone and dexamethasone was 7.8–500 ng/mL, whereas, for hydrocortisone and prednisolone, AMR was 7.8–1000 ng/mL. The method showed an excellent coefficient of determination (r2) >0.990 for betamethasone, hydrocortisone, and prednisolone, while for dexamethasone 0.986. Accuracy and precision (intra/inter days) of these glucocorticoids showed a bias of 6–15 % (<20 %) and a coefficient of variation (CV) of <15 %. For each dilution factor, the integrity of samples was maintained after dilution. The developed method is sensitive and valuable for detecting, quantifying, and confirming the selected glucocorticoids in various quackery formulation powders commonly used in Pakistani setups.

Keywords

• Liquid chromatography-tandem mass spectrometry (LC-MS/MS)
• Glucocorticoids
• Quackery formulations
• Method development
• Validation