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

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 45; no. 5; pp. 1216 - 1220
• Main Authors: Dahint, R., Bender, F.
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.09.1998
• Subjects: Acoustic devices; Acoustic sensors; Antigen-antibody reactions; Biosensors; Chemical and biological sensors; Chemical sensors; Immune system; Macromolecules; Mechanical sensors; Monitoring; Proteins; Sensor systems; Solutions; Surface acoustic waves
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/58.726446

Acoustic plate mode sensors have been used to monitor immunochemical reactions as a function of antigen concentration. In the studies, antibodies were covalently linked to the gold-coated sensing surface via mercaptoethanol, aminosilane, and glutaraldehyde. Two antigen/antibody model systems that differ in their ability to mutually bind one another have been used. For sensor operation at about 150 MHz, a detection limit of approximately 0.5 /spl mu/g/ml was obtained in both cases. No significant difference between the two systems was found for the value of the binding constants. They amount to about 1/spl middot/10/sup 8/ 1/mole and fall well into the range of binding constants reported for homogeneous immunoassays. A comparison of the sensor response obtained for the two model systems shows that about 70% of the immobilized antibodies are active.