Integrated polymer-based Mach-Zehnder interferometer label-free streptavidin biosensor compatible with injection...

Area of Science:

• Biomedical Engineering
• Materials Science
• Optoelectronics

Background:

• Mach-Zehnder interferometers are sensitive optical devices.
• Polymer materials offer advantages for cost-effective sensor fabrication.
• Label-free biosensing eliminates the need for secondary detection molecules.

Purpose of the Study:

• To develop a polymer-based Mach-Zehnder interferometer biosensor.
• To demonstrate label-free, real-time detection of biotin-streptavidin binding.
• To evaluate the sensor's sensitivity and potential for mass production.

Main Methods:

• Fabrication of a high index contrast polymer waveguide.
• Functionalization of the waveguide surface with biotin.
• Utilizing a fluidic system for introducing streptavidin solutions.
• Monitoring binding events via changes in the interferometer's output signal at 1310 nm.

Main Results:

• Successful label-free detection of biotin-streptavidin interactions.
• Achieved a limit of detection for streptavidin as low as 0.1 μg/ml.
• Demonstrated the feasibility of using polymer materials for optical biosensing despite lower surface sensitivity compared to inorganic systems.

Conclusions:

• The polymer Mach-Zehnder interferometer biosensor enables sensitive, label-free detection of biomolecular binding.
• The sensor's compatibility with mass production techniques like injection molding makes it a cost-effective alternative to inorganic sensors.
• This technology holds promise for various diagnostic and research applications.