title: Evaluation of Taylor dispersion injections: determining kinetic/affinity interaction constants and diffusion coefficients in label-free biosensing.
abstract: In label-free biomolecular interaction analysis, a standard injection provides an injection of uniform analyte concentration. An alternative approach exploiting Taylor dispersion produces a continuous analyte titration allowing a full analyte dose response to be recorded in a single injection. The enhanced biophysical characterization that is possible with this new technique is demonstrated using a commercially available surface plasmon resonance-based biosensor. A kinetic interaction model was fitted locally to Taylor dispersion curves for estimation of the analyte diffusion coefficient in addition to affinity/kinetic constants. Statistical confidence in the measured parameters from a single Taylor dispersion injection was comparable to that obtained for global analysis of multiple standard injections. The affinity constants for multisite interactions were resolved with acceptable confidence limits. Importantly, a single analyte injection could be treated as a high-resolution real-time affinity isotherm and was demonstrated using the complex two-site interaction of warfarin with human serum albumin. In all three model interactions tested, the kinetic/affinity constants compared favorably with those obtained from standard kinetic analysis and the estimates of analyte diffusion coefficients were in good agreement with the expected values.
authors.affiliation: FLIR/ICx Nomadics, Oklahoma City, OK 73104, USA. john.quinn@icxt.com
authors.forename: John G
authors.initials: JG
authors.lastname: Quinn
mesh_terms: D015374:Biosensing Techniques; D004058:Diffusion; D006801:Humans; D007700:Kinetics; D008962:Models, Theoretical; D012709:Serum Albumin / Q000737:chemistry; D014859:Warfarin / Q000737:chemistry
chemical_list: D012709:Serum Albumin; D014859:Warfarin