Optical fiber LPG biosensor integrated microfluidic chip for ultrasensitive glucose detection

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Accurate glucose monitoring is crucial for diabetes management.
• Existing glucose sensors face limitations in sensitivity, response time, and detection range.
• Optical fiber sensors offer potential for highly sensitive and label-free detection.

Purpose of the Study:

• To develop an ultrasensitive optical fiber sensor for glucose detection.
• To integrate the sensor into a microfluidic chip for enhanced performance.
• To improve the sensitivity, response time, and detection range of glucose sensing.

Main Methods:

• Fabrication of a small-diameter single-mode fiber (SDSMF) long-period grating (LPG) optical sensor.
• Layer-by-layer (LbL) self-assembly of poly (ethylenimine) (PEI) and poly (acrylic acid) (PAA) multilayer films on the LPG.
• Immobilization of glucose oxidase (GOD) for specific glucose recognition.
• Integration of the biosensor into a microfluidic chip for sample delivery and analysis.

Main Results:

• The SDSMF-LPG biosensor demonstrated ultrasensitive detection of glucose down to 1 nM.
• Integration into the microfluidic chip extended the glucose detection range from 2 µM to 10 µM.
• The response time was significantly reduced from 6 minutes to 70 seconds.

Conclusions:

• The developed optical fiber sensor integrated microfluidic chip offers ultrasensitive and rapid glucose detection.
• The hybrid sensing film and microfluidic integration enhance sensor performance.
• This technology holds promise for advanced glucose monitoring applications.