Temperature Gradient Approach for Rapidly Assessing Sensor Binding Kinetics and Thermodynamics

We report a highly resolved approach for quantitatively measuring the temperature dependence of molecular binding in a sensor format. The method is based on surface plasmon resonance (SPR) imaging measurements made across a spatial temperature gradient. Simultaneous recording of sensor response over the range of temperatures spanned by the gradient avoids many of the complications that arise in the analysis of SPR measurements where temperature is varied. In addition to simplifying quantitative analysis of binding interactions, the method allows the temperature dependence of binding to be monitored as a function of time, and provides a straightforward route for calibrating how temperature varies across the gradient. Using DNA hybridization as an example, we show how the gradient approach can be used to measure the temperature dependence of binding kinetics and thermodynamics (e.g., melt/denaturation profile) in a single experiment.