Using A Fiber Optic Particle Plasmon Resonance Biosensor To Determine Kinetic Constants of Antigen-Antibody Binding Reaction

In this paper, one simple and label-free biosensing method has been developed for determining the binding kinetic constants of antiovalbumin antibody (anti-OVA) and anti-mouse IgG antibody using the fiber optic particle plasmon resonance (FOPPR) biosensor. The FOPPR sensor is based on gold-nanoparticle-modified optical fiber, where the gold nanoparticle surface has been modified by a mixed self-assembled monolayer for conjugation of a molecular probe reporter (ovalbumin or mouse IgG) to dock with the corresponding analyte species such as anti-OVA or anti-mouse IgG. The binding process, occurring when an analyte reacts with a probe molecule immobilized on the optical fiber, can be monitored in real-time. In addition, by assuming a Langmuir-type adsorption isotherm to measure the initial binding rate, the quantitative determination of binding kinetic constants, the association and dissociation rate constants, yields k(a) of (7.21 +/- 0.4) x 10(3) M-1 s(-1) and k(d) of (2.97 +/- 0.1) x 10(-3) s(-1) for OVA/anti-OVA and k(a) of (1.45 +/- 0.2) x 10(6) M-1 s(-1) and k(d) of (2.97 +/- 0.6) x 10(-2) s(-1) for mouse IgG/anti-mouse IgG. We demonstrate that the FOPPR biosensor can study real-time biomolecular interactions.