This assay is primarily used for the in vitro quantitative detection of cortisol levels in human serum and plasma. Cortisol, also known as hydrocortisone or compound F, is a steroid hormone produced by the adrenal cortex and plays a key role in stress response and carbohydrate metabolism. It is synthesized from 11-deoxycortisol through the action of 11β-hydroxylase and follows a circadian rhythm, peaking in the early morning (6–8 a.m.) and reaching its lowest levels around midnight to 2 a.m. Disruptions in this rhythm—due to stress, poor sleep, or lifestyle factors—can lead to elevated cortisol levels, resulting in metabolic disturbances such as increased blood sugar, weight gain, fatigue, reduced libido, and other stress-related symptoms.
