Development of a Simple Voltammetric Method for Estrogens Determination (E1, E2, E3, EE2, and E2Ac) in Pharmaceuticals and Human Urine Using an Unmodified Screen-Printed Carbon Sensor

Abstract

An efficient, fast, and sensitive method for the determination of estrone (E1), 17β-estradiol (E2), estriol (E3), ethinylestradiol (EE2), and β-estradiol-17-acetate (E2Ac) in pharmaceutical formulations and spiked human urine was developed and validated using an unmodified commercial screen-printed carbon electrode. The utilization of linear sweep and square wave voltammetry was compared, and experimental conditions were optimized. In a 6.0 mmol L⁻¹ phosphoric acid solution, the current intensity of the oxidation of the aromatic alcohol was used as the analytical response. The peak potential of each estrogen oxidation signal was found between 0.62 and 0.67 V. The detection limits were found to be for E1, E2, E2Ac, EE2, and E3 were 43, 25, 32, 42, and 44 nmol L⁻¹ using linear sweep voltammetry and 20, 21, 37, 53, and 39 nmol L⁻¹ using square wave voltammetry, respectively. The method was successfully applied to the determination of estrogens in a commercial and spiked drug tablets and spiked human male urine samples. The findings from this study establish a strong basis for the future application of the method in conjunction with high-performance liquid chromatography for the determination of estrogens in samples characterized by complex matrices.