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: 2.22). 02/2008; 373(1):112-20. DOI: 10.1016/j.ab.2007.08.017
Source: PubMed


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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    • "For kinetic titration, several analyte concentrations are injected (usually in increasing order) across the ligand surface in a single binding cycle [13]. In the ligand array format, analyte at one concentration is flowed over a matrix of ligand spots within a single large flow cell [14]. These formats consume less reagent material and require minimal scouting and so can decrease the time required for the experiment. "
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