Enhancing Electrochemical Biosensor Performance for 17β-Estradiol Determination with Short Split-Aptamers.

Area of Science:

• Environmental Science
• Analytical Chemistry
• Biotechnology

Background:

• Chronic exposure to 17β-estradiol (E2) disrupts endocrine systems and causes long-term health issues.
• Effective detection of E2 in water is crucial for environmental and public health.

Purpose of the Study:

• To develop a rapid and sensitive electrochemical biosensor for detecting E2 in water samples.
• To utilize split DNA aptamers immobilized on a novel electrode surface for enhanced detection.

Main Methods:

• Fabrication of an electrode modified with polypyrrole nanowires and poly(methacrylic acid-co-n butyl acrylate-succinimide) microspheres.
• Immobilization of truncated split DNA aptamers (12-mer and 14-mer) on the microspheres.
• Detection of E2 via differential pulse voltammetry using ferrocyanide as a redox indicator, based on aptamer-E2 complex formation.

Main Results:

• The aptasensor detected E2 in the concentration range of 1 × 10⁻⁴ M to 1 × 10⁻¹² M (R² = 0.9772).
• Achieved a low detection limit of 4.8 × 10⁻¹³ M for E2.
• Demonstrated high accuracy in real water samples (97-104% recovery) and excellent correlation with HPLC (R² = 0.9999).
• Split aptamer design enhanced selectivity against potential interferents.

Conclusions:

• The developed electrochemical biosensor offers a rapid, sensitive, and selective method for E2 detection in water.
• The use of split DNA aptamers significantly improves aptasensor performance.
• This technology holds promise for environmental monitoring and protecting public health from endocrine-disrupting chemicals.