A rapid and sensitive aptamer-based biosensor for beta-lactoglobulin in milk

Area of Science:

• Analytical Chemistry
• Biochemistry
• Food Science

Background:

• Beta-lactoglobulin (β-Lg) is a major milk allergen, necessitating accurate quantification for allergy risk assessment.
• Assessing allergenic potential in dairy products relies on precise measurement of β-Lg levels.

Purpose of the Study:

• To develop a rapid and sensitive aptasensor for the detection of beta-lactoglobulin (β-Lg).
• To evaluate the performance of the aptasensor for quantitative assessment of β-Lg in milk samples.

Main Methods:

• Screening of a specific aptamer (β-Lg-01) using magnetic bead SELEX (MB-SELEX).
• Development of a bio-layer interferometry (BLI)-based aptasensor for β-Lg detection.
• Validation of the aptasensor using milk samples, assessing limit of detection, linear range, and recovery rate.

Main Results:

• Aptamer β-Lg-01 exhibited a high affinity for β-Lg with a K_D of 28.6 nM.
• The BLI-based aptasensor achieved a limit of detection of 0.3 ng mL^-1.
• The aptasensor demonstrated a linear range of 1.5 ng mL^-1-15 μg mL^-1 and recovery rates of 102-116% in milk samples.
• Detection and risk assessment of β-Lg were achieved within 10 minutes.

Conclusions:

• A novel BLI-based aptasensor enables rapid and sensitive detection of β-Lg.
• This aptasensor is a promising tool for evaluating the allergenic potential of dairy products.
• The developed method offers efficient risk assessment for milk allergies.