[Oriented immobilization of human IgG by protein A on imaging ellipsometry biosensor]

Area of Science:

• Biomolecular Engineering
• Surface Chemistry
• Analytical Chemistry

Context:

• Biosensors are crucial for detecting biomolecules without labels.
• Optical imaging ellipsometry offers label-free detection of surface biomolecule concentrations.
• Antibody immobilization strategies are key to biosensor performance.

Purpose:

• To investigate the feasibility of using protein A for antibody immobilization on silicon surfaces for imaging ellipsometry biosensors.
• To compare the binding efficiency of antibodies immobilized via protein A versus direct immobilization.
• To assess the potential of protein A surface modification for developing sensitive immunoassays.

Summary:

• Protein A effectively immobilizes antibodies (anti-IgG) onto silicon surfaces for imaging ellipsometry.
• Protein A-mediated immobilization resulted in higher binding of human IgG and polyclonal antibodies compared to direct immobilization.
• Protein A may prevent non-specific binding and preserve the native configuration of immobilized biomolecules.

Impact:

• Protein A modification enhances the capacity of biosensors to immobilize diverse antibodies targeting Fc regions.
• The combination of imaging ellipsometry and protein A offers a promising platform for high-sensitivity immunoassays.
• This approach facilitates label-free detection of biomolecules with improved performance.