Antibody binding to a functionalized supported lipid layer: a direct acoustic immunosensor

Area of Science:

• Biosensing
• Biophysics
• Surface Chemistry

Background:

• Development of sensitive and specific biosensors is crucial for diagnostics and research.
• Acoustic wave devices offer label-free detection capabilities.
• Supported lipid bilayers provide a versatile platform for bioreceptor immobilization.

Purpose of the Study:

• To develop a direct immunosensor based on acoustic wave technology.
• To characterize the binding kinetics and specificity of antibody-antigen interactions.
• To evaluate the performance of a supported lipid bilayer as a biorecognition surface.

Main Methods:

• Fabrication of a Love wave acoustic waveguide device.
• Immobilization of a biotinylated supported lipid layer on a gold surface.
• Specific binding of streptavidin and biotinylated goat IgG.
• Detection of rabbit anti-goat IgG using the developed immunosensor.
• Kinetic analysis via binding isotherms and time-resolved measurements.
• Comparative analysis with surface plasmon resonance (SPR).

Main Results:

• The immunosensor successfully detected rabbit anti-goat IgG in the concentration range of 3 x 10(-8) - 10(-6) M.
• Binding and rate constants for the antibody-antigen reaction were determined.
• The supported lipid bilayer demonstrated effective suppression of nonspecific binding.
• Quantitative correlation between immunosensor response and mass binding was established using SPR.

Conclusions:

• A direct acoustic wave immunosensor with a supported lipid bilayer is effective for antibody detection.
• The developed platform allows for kinetic and specificity studies of biomolecular interactions.
• This technology shows promise for sensitive and specific label-free biosensing applications.