A concentration dependent study of acoustic plate mode immunosensor response using antigen/antibody systems with...

Area of Science:

• Biosensing
• Immunochemistry
• Surface Science

Background:

• Acoustic plate mode sensors offer label-free detection of biomolecular interactions.
• Monitoring immunochemical reactions requires sensitive and quantitative methods.

Purpose of the Study:

• To evaluate acoustic plate mode sensors for monitoring immunochemical reactions.
• To determine the sensor's detection limit and binding constants for antigen/antibody systems.
• To assess the activity of immobilized antibodies on the sensor surface.

Main Methods:

• Covalent immobilization of antibodies onto a gold-coated sensing surface using mercaptoethanol, aminosilane, and glutaraldehyde.
• Utilizing two distinct antigen/antibody model systems with varying binding affinities.
• Operating the sensor at approximately 150 MHz to measure binding events.

Main Results:

• A detection limit of approximately 0.5 microg/ml was achieved for both model systems.
• Binding constants were found to be approximately 1.10(8) 1/mole, comparable to homogeneous immunoassays.
• Approximately 70% of the immobilized antibodies were found to be active.

Conclusions:

• Acoustic plate mode sensors are suitable for quantitative monitoring of immunochemical reactions.
• The sensor demonstrates high sensitivity and reliable binding constant determination.
• The immobilization strategy results in a high percentage of active antibodies.