Biofunctionalization of Multiplexed Silicon Photonic Biosensors

Area of Science:

• Nanotechnology and Materials Science
• Biomedical Engineering
• Sensor Technology

Background:

• Silicon photonic (SiP) sensors are scalable, low-cost platforms for decentralized diagnostics.
• CMOS-compatible fabrication allows for miniaturization and mass production of SiP devices.
• Sensor performance is critically dependent on the biofunctionalization of the SiP surface.

Purpose of the Study:

• To review biofunctionalization needs for SiP biosensors, including sensitivity, specificity, cost, shelf-stability, and replicability.
• To establish performance criteria for evaluating biofunctionalization strategies.
• To benchmark various biofunctionalization techniques against these criteria.

Main Methods:

• Evaluation of bioreceptor selection: antibodies, aptamers, nucleic acid probes, molecularly imprinted polymers, peptides, glycans, and lectins.
• Comparison of immobilization strategies: adsorption, bioaffinity, and covalent chemistries.
• Benchmarking of biopatterning techniques: microcontact printing, spotting, microfluidic patterning, inkjet printing, and microfluidic probes.

Main Results:

• Detailed comparison of different bioreceptors based on established performance criteria.
• Analysis of the advantages and disadvantages of various immobilization chemistries for SiP surfaces.
• Assessment of spatial control and multiplexing capabilities offered by different biopatterning methods.

Conclusions:

• Effective biofunctionalization is key to realizing the full potential of SiP biosensors for diagnostics.
• The choice of bioreceptor, immobilization strategy, and patterning technique significantly impacts sensor performance.
• This review provides a framework for selecting optimal biofunctionalization approaches for SiP biosensor development.