Micro-capillary-based self-referencing surface plasmon resonance biosensor for determination of transferrin

Area of Science:

• Biosensing
• Optical Spectroscopy
• Biochemistry

Background:

• Surface Plasmon Resonance (SPR) is a label-free optical technique for detecting molecular interactions.
• Existing SPR biosensors can be affected by environmental factors like temperature, impacting detection accuracy.
• Transferrin detection is crucial for diagnosing various medical conditions.

Purpose of the Study:

• To develop a novel self-referencing SPR biosensor for enhanced transferrin detection.
• To utilize the Fabry-Perot (FP) mode for temperature compensation in SPR measurements.
• To demonstrate real-time monitoring of transferrin-anti-transferrin interactions.

Main Methods:

• Fabrication of a micro-capillary based SPR biosensor with a gold film coating.
• Excitation of SPR mode on the gold film and FP mode within the de-ionized water-filled capillary.
• Utilizing the temperature-sensitive FP mode as a referencing signal to correct for temperature variations.
• Real-time measurement of transferrin protein concentration and its binding with anti-transferrin.

Main Results:

• The biosensor achieved a high sensitivity of 1783.943 nm/RIU and a resolution of 7.287×10^-5 RIU.
• The self-referencing capability effectively compensated for temperature fluctuations.
• Demonstrated real-time monitoring of transferrin-anti-transferrin interactions over a concentration range of 0-5.228 μM.
• The developed biosensor is simple, low-cost, and highly sensitive.

Conclusions:

• The novel self-referencing SPR biosensor offers a robust and accurate method for transferrin detection.
• The integrated FP mode provides effective temperature compensation, improving biosensor reliability.
• This technology holds potential for sensitive, real-time biosensing applications in diagnostics and research.