Highly sensitive surface plasmon resonance biosensor based on a low-index polymer optical fiber

Area of Science:

• Optoelectronics
• Chemical Sensing
• Biomedical Engineering

Background:

• Surface Plasmon Resonance (SPR) is a powerful optical phenomenon for sensing.
• Polymer optical fibers offer flexibility and cost-effectiveness for sensor development.
• Low-index materials are crucial for enhancing SPR sensor sensitivity.

Purpose of the Study:

• To propose and demonstrate a highly sensitive refractive index sensor.
• To utilize a side-polished low-index polymer optical fiber for enhanced biosensing.
• To investigate the sensor's performance for aqueous solutions and glucose detection.

Main Methods:

• Fabrication of the sensor by coating a 55-nm-thick gold film on a polished perfluorinated polymer optical fiber.
• Utilizing surface plasmon resonance in the optical fiber for refractive index measurements.
• Characterization of sensor sensitivity and figure of merit in aqueous solutions.

Main Results:

• Theoretical sensitivity reached ~44567 nm/RIU for aqueous solutions.
• Experimental sensitivity achieved ~22779 nm/RIU at a refractive index of 1.335.
• Demonstrated glucose sensing with an averaged sensitivity of 24.50 nm/wt% (0.46 nm/mM).

Conclusions:

• The developed sensor exhibits high sensitivity and a figure of merit of 61.2.
• The device shows potential for cost-effective bio- and chemical-sensing applications.
• The low-index polymer optical fiber SPR sensor is a promising platform for sensitive detection.