Abstract

Binding Kinetic Constants Measurement by Using Fiber Optic Particle Plasmon Resonance Biosensor

Shau-Chun Wang, Professor and Director, Department of Chemistry and Biochemistry and the Center for Nano BioDetection, National Chung Cheng University

Biosensing methods have been a popular means to measure the binding affinity and rate constants of immuno-logical reactions. In particular, the quantitative investigation of binding kinetics provides important information regarding the interactions between the docking target molecule and the counterpart probe molecule. Fiber optic particle plasmon resonance (FOPPR) biosensor, one simple and label-free sensing platform, has been successfully used to determine binding kinetic constants. The FOPPR biosensor is based on an optical fiber modified on gold nanoparticles, where the surface of gold nanoparticles has been conjugated by a mixed self-assembled monolayer (SAM) and a molecular probe reporter to dock with the corresponding analyte species. The binding process is recorded in static mode when analyte solution is loaded in one static sensing cell. The ability to analyse biomolecules without flow may be especially useful when an experiment only has a small amount of analyte available to characterize a biomolecular interaction. We compare FOPPR biosensor with commercialized Biacore 3000 SPR biosensor to determine the binding kinetic constants, which is limited by analyte injection flow rate and the probe concentration on the chip in Biacore 3000 SPR biosensor whereas FOPPR is not affected by these two effects. In addition, we established the general mathematical model to estimate the binding kinetic rate constants based on the pseudo-first-order model. We will discuss the agreement of obtained association rate constants (ka) and dissociation rate constants (kd) of anti-ovalbumin with ovalbumin and IgG binding with anti-IgG, between the computational results using our mathematical model, and the measured values.