User:Nathan.gillock/sandbox

=OneStep= Onestep is the application of Taylor dispersion to a microfluidic injection system. It is an injection methodology employed in surface plasmon resonance (SPR). Taylor dispersion is exploited to generate an analyte concentration gradient that provides a high-resolution dose response. Analyte gradients conform to Taylor dispersion theory for accurate modeling of the analyte concentration during the titration. A full analyte titration over three to four orders of magnitude in concentration is recorded within a few minutes.

Formerly Taylor dispersion injections.

=Applications=

The major application of OneStep is decreasing the time required to determine reliable kinetic values for an interaction or high throughput screen. An entire dose response plot can be obtained from a single curve instead of constructed from multiple curves each at different fixed concentrations. It eliminates the need for secondary screening. This can also be applied to thermodynamic assays to get coefficients more rapidly.

Several secondary applications of OneStep exist. These are the determination of analyte diffusion coefficient, retention factor, and the time-dependent resolution of multisite binding.

Diffusion Coefficient
The diffusion coefficient $$D$$ can be used to determine how the molecules self interact as they move through the fluidics. This is represented as an aggregation number and represents the multimeric state of the analyte. This can be determined either alongside kinetics in a binding interaction study or independently without a binding partner.

Retention Factor
A retention factor indicates an interaction between the microfluidic tubing carrying sample and the sample itself. OneStep allows empirical determination of this factor if it exists which can then be implemented in the model fit to the data. This essentially eliminates the effect, giving more accurate kinetic values.

Multisite binding
Because OneStep adds concentration over time to SPR analysis, it gives excellent separation of multiple binding site information. Stronger binding sites show up earlier in the curve when the concentrations are low and weaker binding show up later when the higher concentrations required get to the flow cell. This allows

=Modeling and Analysis=

=See Also=
 * Surface Plasmon Resonance
 * Taylor Dispersion

=References=


 * John G. Quinn, Modeling Taylor dispersion injections: Determination of kinetic/affinity interaction constants and diffusion coefficients in label-free biosensing, Analytical Biochemistry, Volume 421, Issue 2, 15 February 2012, Pages 391-400, ISSN 0003-2697, 10.1016/j.ab.2011.11.024.
 * John G. Quinn, Evaluation of Taylor dispersion injections: Determining kinetic/affinity interaction constants and diffusion coefficients in label-free biosensing, Analytical Biochemistry, Volume 421, Issue 2, 15 February 2012, Pages 401-410, ISSN 0003-2697, 10.1016/j.ab.2011.11.023.
 * Taylor 1-X