Development of an immunosensor for quantifying zebrafish vitellogenin based on the Octet system

Area of Science:

• Environmental Toxicology
• Biomarker Development
• Biosensor Technology

Background:

• Vitellogenin (Vtg) is a crucial biomarker for detecting environmental estrogens.
• Existing immunoassay techniques for Vtg quantification can be time-consuming and complex.
• There is a need for rapid, reliable methods to assess estrogenic compound exposure in aquatic organisms.

Purpose of the Study:

• To develop and validate a novel immunosensor for quantifying zebrafish Vtg using the Octet system.
• To assess the sensor's performance, including its linear range, reproducibility, and speed.
• To demonstrate the immunosensor's utility in detecting Vtg induction in response to estrogenic exposure.

Main Methods:

• Development of an immunosensor by immobilizing anti-lipovitellin (Lv) antibody onto Protein A sensors.
• Utilizing the Octet system for real-time kinetic measurement of antigen-antibody interactions.
• Quantification of Vtg in zebrafish samples by correlating binding rates with a standard curve.
• Validation of the immunosensor by measuring Vtg induction in zebrafish exposed to 17β-estradiol (E2).

Main Results:

• The immunosensor demonstrated a wide linear range (78–5000 ng/mL) and high reproducibility (inter-assay CV: 0.66–1.97%).
• Rapid Vtg quantification was achieved within 15 minutes, significantly faster than conventional methods.
• The sensor successfully detected Vtg induction in zebrafish exposed to E2, confirming its efficacy.
• Protein A sensors showed high reusability, enhancing assay cost-effectiveness.

Conclusions:

• The developed Octet system-based immunosensor offers a simple, rapid, and reproducible method for zebrafish Vtg quantification.
• This biosensor is a valuable tool for ecotoxicological research, enabling efficient assessment of environmental estrogen exposure.
• The technology facilitates high-throughput screening and monitoring of endocrine-disrupting chemicals in aquatic ecosystems.