GPE/MIL-100(Fe) composite-enhanced electrochemical sensor for estradiol detection in liquid environments

Estradiol (E2) is a steroid hormone that has garnered widespread global attention as an emerging pollutant due to its potential to cause endocrine disruption in organisms upon concentration changes. This experiment achieves highly efficient detection of estradiol based on screen-printed electrodes (SPEs) and a graphene (GPE)/MIL-100(Fe) composite material. The GPE/MIL- 100(Fe) composite, characterized by a rich porous structure, was synthesized via a hydrothermal method, and the modified electrode was prepared using the drop-coating technique. The GPE/MIL-100(Fe) composite was characterized by SEM, XRD, FTIR, and XPS to confirm its structure, composition, and properties. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and chronoamperometry (CA) were employed to enable continuous monitoring of estradiol in liquid environments. The modified electrode demonstrated significant electrocatalytic activity, exhibiting high sensitivity within a linear range of 2.0 nmol/ mL to 140 nmol/mL, with a practical detection limit (LOD) of 0.002 μmol/mL. The innovation of this study lies in leveraging the synergistic effect of GPE/MIL-100(Fe) to enhance the detection performance for estradiol. In the detection of actual samples such as urine (spiked recovery rate: 103.3% -110.9%) and pond water (spiked recovery rate: 96.7% -110.0%), clear characteristic peaks and good sensitivity for estradiol were observed.