Extracting kinetic rate constants from surface plasmon resonance array systems.

Center for Biomolecular Interaction Analysis, School of Medicine, University of Utah, Salt Lake City, UT 84132, USA.
Analytical Biochemistry (Impact Factor: 2.58). 02/2008; 373(1):112-20. DOI:10.1016/j.ab.2007.08.017
Source: PubMed

ABSTRACT Surface plasmon resonance imaging systems, such as Flexchip from Biacore, are capable of monitoring hundreds of reaction spots simultaneously within a single flow cell. Interpreting the binding kinetics in a large-format flow cell presents a number of potential challenges, including accounting for mass transport effects and spot-to-spot sample depletion. We employed a combination of computer simulations and experimentation to characterize these effects across the spotted array and established that a simple two-compartment model may be used to accurately extract intrinsic rate constants from the array under mass transport-limited conditions. Using antibody systems, we demonstrate that the spot-to-spot variability in the binding kinetics was <9%. We also illustrate the advantage of globally fitting binding data from multiple spots within an array for a system that is mass transport limited.

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