Laser Reflectometry Technique Applied to Study of Antibody Adhesion Kinetic

RIQUELME, BD; RIUS, SP; BOZZA, VV; RASIA, RJ

Rosario- Santa Fe

Congreso; III Congreso Rosarino- XVIII Reunión Anual de la Sociedad de Biología de Rosario,; 1999

Sociedad Biología de Rosario

Study of biomolecular interaction dynamic and relations between their structure and function in very important for understanding of biological systems, This technique as the surface plasmon resonance technique, can give information about the interaction kinetic, stechiometry of molecular binding (to an interface solid/liquid), and the concentration of molecule in a solution. This method offers detailed and accurate determination of real-time adsorption kinetics of protein without labeling of protein. When the polarized light (parallel to the plane of incidence) is reflected on a solid surface (silicon), the reflectance has a minimum at the principal incidence angle (qp). According as the proteins are absorbed over the surface the reflectance (at qp) increases. Therefore, the temporal register of reflected intensity gives curves representing the binding kinetics of antibody in real-time. The technique is highly sensitive because the large difference in the refractive index between silicon and organic material; about 0,1 ug/cm2 of absorbed protein can be detected. This method was applied to study the adhesion kinetics of monoclonal anti-A and anti-AB antibodies at surface of a silicon wafer. The mathematical analysis of results would suggest that the antibody association occurs according to classical Langmuir surface adsorption.