Light-sheet skew rays enhanced U-shaped fiber-optic fluorescent immunosensor for Microcystin-LR

Area of Science:

• Optoelectronics
• Biomedical Engineering
• Environmental Science

Background:

• Microcystin-LR (MC-LR) poses significant risks to aquatic ecosystems and human health.
• Existing detection methods for MC-LR often lack the sensitivity and real-time capabilities required for effective monitoring.
• Fiber-optic sensors offer potential for sensitive and portable analytical tools.

Purpose of the Study:

• To design and demonstrate a novel U-shaped fiber-optic evanescent-wave fluorescent immunosensor for sensitive, real-time MC-LR detection.
• To enhance light-matter interactions using light-sheet excitation of skew rays within the fiber.
• To validate the sensor's performance in real environmental water samples.

Main Methods:

• A U-shaped fiber-optic probe was engineered for enhanced evanescent wave interaction.
• Light-sheet excitation of skew rays was implemented to maximize fluorophore interaction.
• An indirect competitive immunoassay principle was employed for MC-LR quantification.
• The sensor's sensitivity was compared against collimated skew ray excitation.

Main Results:

• The developed immunosensor achieved a 16-fold increase in fluorescence sensitivity compared to collimated skew ray excitation.
• Real-time detection of MC-LR in environmental water samples was successfully demonstrated.
• Recovery rates for spiked MC-LR in water samples ranged from 85% to 112%.

Conclusions:

• The integration of light-sheet skew rays with a U-shaped fiber-optic probe significantly enhances sensitivity for MC-LR detection.
• This novel immunosensor provides a sensitive, real-time analytical tool suitable for environmental monitoring, food safety, and clinical diagnostics.
• The study advances the field of fiber-optic sensors through innovative experimental design.