Gonyautoxin 1/4 aptamers with high-affinity and high-specificity: From efficient selection to aptasensor application.

Area of Science:

• Marine Biology
• Biotechnology
• Analytical Chemistry

Background:

• Gonyautoxin 1/4 (GTX1/4) are potent marine neurotoxins posing significant public health risks.
• Existing detection methods for GTX1/4 face ethical and technical challenges, necessitating alternative approaches for regulatory monitoring.

Purpose of the Study:

• To develop and characterize a high-affinity aptamer specific for GTX1/4.
• To construct a label-free, real-time optical aptasensor for GTX1/4 detection.
• To evaluate the aptasensor's performance in terms of sensitivity, specificity, and application in real samples.

Main Methods:

• Selection and optimization of a GTX1/4-specific aptamer using the advanced GO-SELEX screening technology.
• Truncation of the aptamer to identify a core sequence with high affinity (Kd of 17.7 nM).
• Construction of a label-free optical biolayer interferometry (BLI) aptasensor using the optimized aptamer.

Main Results:

• The aptasensor demonstrated a broad detection range (0.2–200 ng/mL) and a low limit of detection (50 pg/mL) for GTX1/4.
• High specificity for GTX1/4 was observed, with no cross-reactivity to other marine toxins.
• The aptasensor successfully detected GTX1/4 in spiked shellfish samples, showing good reproducibility and stability.

Conclusions:

• A novel aptamer-based optical biosensor provides a promising alternative for the rapid and accurate detection of the marine biotoxin GTX1/4.
• The developed aptasensor addresses limitations of traditional methods, offering improved sensitivity and specificity for regulatory monitoring.
• This technology has the potential to enhance food safety by enabling efficient detection of paralytic shellfish toxins.