Bidirectional Drive Reverse-Phase Enhanced Fluorescence Lateral Flow Immunoassay with Spectral Overlap and...

Area of Science:

• Analytical Chemistry
• Biochemistry
• Materials Science

Background:

• Competitive lateral flow immunoassays (LFIA) are increasingly utilizing reverse-phase enhanced fluorescence (turn-on mode) for sensitive detection.
• Key factors for effective fluorescence turn-on include designing quenchers, selecting fluorescence donors, and optimizing quenching modes.

Purpose of the Study:

• To develop a highly sensitive and accurate competitive LFIA for deoxynivalenol (DON) detection.
• To investigate the efficacy of Au@MnO2 nanoparticles as quenchers and AuNCs as fluorescence donors in a turn-on fluorescence mode.
• To establish an immunological network for improved quantitative balance and sensitivity.

Main Methods:

• Utilized Au@MnO2 nanoparticles as quenchers and AuNCs as fluorescence donors.
• Developed a competitive LFIA with a fluorescent turn-on mode and an immunological network.
• Optimized spectral overlap between absorption and emission spectra for enhanced signal.

Main Results:

• The fluorescent turn-on mode achieved an 11.65-fold sensitivity enhancement (0.0509 ng/mL) over the colorimetric mode (0.593 ng/mL).
• The immunological network enhanced sensitivity by 5.08-fold compared to the non-network mode (0.259 ng/mL).
• Satisfactory recovery rates (93.33-109.02%) were observed in real food samples (maize, wheat, oat).

Conclusions:

• The developed Au@MnO2-GAB-CFLFIA offers a novel and efficient strategy for sensitive DON detection.
• Spectral overlap and quantitative balance are crucial for optimizing reverse-phase enhanced fluorescence LFIA.
• This method provides a rapid and accurate approach for toxin analysis in agricultural products.