Kinetic Analysis of Antibody–Antigen Interactions using Phase-Detection-Based Surface Plasmon Resonance Sensor System

Abstract

Surface plasmon resonance (SPR) biosensors have the advantage of being highly sensitive, requiring no fluorescent-labeled analytes or receptors, and being capable of monitoring molecular interactions in real time. Thus, they have been widely used in determining the dynamics of molecular interactions. However, owing to the lack of experience in employing phase-detected SPR, there have been no research reports on the determination of affinity constant for antigen-antibody interactions. In this study, we used a custom-made phase-detection SPR sensor system to investigate the kinetic parameters of an antibody binding to an antigen immobilized on a CM5 sensor chip. This system provided real-time measurements of molecular interactions on the sensor chip. The association and dissociation rate constants and the corresponding affinity were obtained.

Wireless poly(dimethylsiloxane) quartz-crystal-microbalance biosensor chip fabricated by nanoimprint lithography for micropump integration aiming at application in lab-on-a-chip

“…The SPR sensor measures the intensity of light reflected from a gold thin film formed on the surface of a high-refractive-index prism when the lightwave enters at the total reflection angle or larger. 11) When the gold film is sufficiently thin (about 50 to 100 nm), the lightwave passes through the gold thin film and generates an evanescent field on the metal surface. At the same time, the surface plasmons are excited at the interface between the gold thin film and the analyte immobilized on the surface of the gold thin film.…”

Biosensor Based on Degree of Coherence of A Pair of Surface Plasma Waves

“…Previously, a phase-sensitive detection scheme was proposed and its effectiveness was demonstrated. − However, a limited dynamic range of the phase detection method, which is defined by the range of detectable concentration of analyte such as protein in solution, has a consequence that only small biomolecules in low concentration can be measured. In other publications, an amplitude-sensitive interferometric SPRB was proposed that is able to provide a wide dynamic range and also a high detection sensitivity. − Recently, Chou et al proposed a “paired surface plasma wave biosensor” (PSPWB), which uses a Zeeman He–Ne laser outputting a pair of linearly polarized two-frequency laser beam. To improve further the detection sensitivity in an amplitude-sensitive PSPWB, a real-time normalization of the detected heterodyne signal was accomplished using a reference heterodyne signal; this effectively reduces the excess noise from laser intensity fluctuations and improves the detection sensitivity significantly.…”