Quantum Dot-Sensitised Estrogen Receptor-α-Based Biosensor for 17β-Estradiol

Area of Science:

• Environmental Science
• Biotechnology
• Analytical Chemistry

Background:

• 17β-estradiol (E2) is a potent estrogenic endocrine-disrupting compound (e-EDC) found in environmental water systems, posing significant health risks.
• Accurate determination of E2 levels is critical for effective wastewater treatment and environmental pollution management.

Purpose of the Study:

• To develop a highly selective and sensitive biosensor for the determination of 17β-estradiol (E2).
• To leverage the specific binding affinity between estrogen receptor-α (ER-α) and E2 for sensor development.

Main Methods:

• Fabrication of an electroactive sensor platform using a gold disk electrode functionalized with 3-mercaptopropionic acid-capped tin selenide (SnSe-3MPA) quantum dots.
• Immobilization of estrogen receptor-α (ER-α) onto the SnSe-3MPA/AuE platform via amide chemistry to create the ER-α/SnSe-3MPA/AuE biosensor.
• Electrochemical detection of E2 using square-wave voltammetry (SWV).

Main Results:

• The developed ER-α/SnSe-3MPA/AuE biosensor demonstrated a formal potential of 217 ± 12 mV for E2 monitoring.
• The biosensor exhibited a dynamic linear range (DLR) of 1.0-8.0 nM (R² = 0.99) and a limit of detection (LOD) of 1.69 nM.
• High selectivity for E2 and good recovery rates were observed in milk samples, indicating practical applicability.

Conclusions:

• The ER-α/SnSe-3MPA/AuE biosensor provides a sensitive and selective method for E2 detection.
• This biosensor is a promising tool for environmental monitoring and wastewater treatment applications.
• The study highlights the potential of quantum dot-based biosensors for detecting endocrine-disrupting compounds.