Hydrocortisone UV-Vis Spectrophotometric Study: Stability, Determination of Its Acidity Constants and Quantification

Abstract

Hydrocortisone is a glucocorticoid-type hormone produced naturally by the organism, such that it maintains the body functional during physical or mental stress episodes. The present work focuses on the UV-Vis spectrophotometric assessment of the chemical stability of hydrocortisone in an aqueous medium during the time of analysis, determination of its acidity constants through a robust methodology that involves the usage of SQUAD software and validation of an analytical method to determine hydrocortisone by means of UV-Vis spectrophotometry, in pharmaceuticals. The acidity constant was determined as pK_a 11.45 ± 0.02 (298 K), and the molar absorptivity coefficients and the molar absorptivity coefficients of the species involved in this acidity equilibrium were also determined as a function of the wavelength. The analytical method developed attained detection and quantification limits of 386 ± 3 and 1280 ± 10 nM, respectively, whereas the validation allows reliable quantification of hydrocortisone in pharmaceuticals.