Integration of microfluidics with a four-channel integrated optical Young interferometer immunosensor

Area of Science:

• Optoelectronics
• Microfluidics
• Biomedical Engineering

Background:

• Integrated optical (IO) Young interferometer (YI) sensors offer label-free detection capabilities.
• Traditional bulky cuvette systems often suffer from slow response times and limited sensitivity.
• Microfluidic integration presents an opportunity to enhance the performance of optical biosensors.

Purpose of the Study:

• To develop and characterize a hybrid microfluidic-IO YI system for enhanced optical sensing.
• To evaluate the system's performance in terms of response time, accuracy, and resolution.
• To demonstrate the system's feasibility for label-free immunosensing applications.

Main Methods:

• Fabrication of a microfluidic system with four microchannels on a glass plate.
• Bonding the microfluidic system to a four-channel IO YI chip.
• Experimental testing using refractive index changes and anti-human serum albumin/human serum albumin (alpha-HSA/HSA) immunoreactions.

Main Results:

• Reduced sensor response time from 100s to 4s compared to cuvette systems.
• Achieved a refractive index resolution of 6 x 10(-8) and protein mass coverage resolution of 20 fg/mm2.
• Demonstrated improved discrimination between bulk refractive index changes and layer formation for higher accuracy.

Conclusions:

• The hybrid microfluidic-IO YI system enables rapid and highly sensitive label-free biosensing.
• The system is suitable for immunosensing applications, offering precise kinetic analysis.
• This technology holds promise for advancing high-accuracy biomolecular detection.