Application of a cobalt(II) coordination complex in the electrochemical detection and quantification of adrenaline

Adrenaline, also known as epinephrine, is a hormone and neurotransmitter produced by the adrenal glands. In the bloodstream, adrenaline affects vital physiological functions such as heart rate, blood pressure and glycogen breakdown. Abnormal adrenaline levels can indicate underlying health disorders, with increases often seen in emotional or physical stress and diseases such as cancer and Parkinson's disease. Electrochemical methods are effective for detecting neurotransmitters, as they are fast-responding, easy to use, and highly sensitive. In this context, a novel electrochemical sensor has been developed for the precise and selective detection of adrenaline. The sensor, based on a glassy carbon electrode modified with a cobalt(II) coordination complex, showed improved electrochemical performance for adrenaline detection, with a linear response range of 0.1 to 2.0 μM, a detection limit of 0.09 μM, and a sensitivity of 26.92 nA μM-1. When analysing real samples, the modified electrode showed favourable electroanalytical properties for the oxidation of adrenaline and demonstrated stability, reproducibility and suitability for use in pharmaceutical formulations. The selectivity of the sensor was confirmed by interference studies, which showed negligible response changes in the presence of common interferents, except for ascorbic acid (vitamin C).