Double-layer core-satellite magnetic SERS aptasensor for ultrasensitive and interference-free tryptamine detection

Area of Science:

• Analytical Chemistry
• Nanotechnology
• Biosensors

Background:

• Excessive dietary tryptamine poses health risks, necessitating advanced detection methods.
• Surface-enhanced Raman Spectroscopy (SERS) aptasensors offer high sensitivity but suffer from instability and poor anti-interference.
• Existing detection technologies lack the required efficiency, sensitivity, and speed for tryptamine analysis.

Purpose of the Study:

• To develop a stable and highly sensitive SERS aptasensor for tryptamine detection.
• To overcome the limitations of instability and poor anti-interference in current SERS aptasensors.
• To create a reliable analytical method for detecting tryptamine in various food matrices.

Main Methods:

• Fabrication of a two-layer core-satellite magnetic SERS aptasensor using Fe3O4@Au nanoparticles functionalized with aptamers.
• Utilized magnetic separation for efficient probe collection and concentration.
• Employed 4-mercaptobenzonitrile as a Raman reporter in the "biological-silent" spectral region.

Main Results:

• The aptasensor demonstrated a broad linear range (0.001–100 mg L−1) and a low detection limit (0.39 × 10−3 mg L−1) for tryptamine.
• The core-satellite structure provided enhanced SERS signals and improved stability.
• The sensor showed high consistency with HPLC in analyzing tryptamine in real food samples (liquor, wine, vinegar).

Conclusions:

• The developed magnetic SERS aptasensor provides a sensitive, stable, and rapid method for tryptamine detection.
• This technology holds significant potential for ensuring food safety and detecting foodborne threats.
• The analytical method shows broad applicability in complex food matrices.