Year: 2025
Type: article
Abstract: Estrogens are cholesterol-derived hormones, with four endogenous estrogens being presented in the scientific literature, namely, estradiol, estrone, estriol, and estetrol. In this study, we aim to obtain a complete thermoanalytical profile for the three most important endogenous estrogens: estradiol, estriol, and estrone. To achieve this, the TG/DTG were registered in non-isothermal conditions at five different heating rates (β = 2, 4, 6, 8, and 10 °C min−1). To describe the mechanisms of the degradation processes, a complex kinetic analysis was performed by applying a preliminary method (ASTM E698), two isoconversional methods (Flynn–Wall–Ozawa and Friedman), and the non-parametric kinetic method. The results indicate that estradiol undergoes a single-step degradation process, while estriol and estrone present a complex degradation process. The determination of the shelf life of pharmaceutical products represents a critical factor in ensuring their safety and efficacy. This parameter can be estimated from the activation energy derived from non-isothermal experiments through the application of the Arrhenius equation and appropriate kinetic models.
Authors: Amalia Ridichie, Adriana Ledeţi, Cosmina Bengescu, Laura Sbârcea, Răzvan Adrian Bertici, Denisa Laura Ivan, Gabriela Vlase, Titus Vlase, Francisc Peter, Ionuţ Ledeţi
Language: English
Topic: Thermal and Kinetic Analysis
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,207
OpenAlex ID: W4416500474