Label-Free Microfluidic Characterization of Temperature-Dependent Biomolecular Interactions
News Oct 13, 2011
Solvated L-arginine vasopressin (AVP) and its immobilized RNA aptamer (spiegelmer) were allowed to achieve equilibrium binding in a microchip at a series of selected temperatures. Unbound AVP were collected and analyzed with matrix-assisted laser desorption∕ionization mass spectrometry (MALDI-MS), yielding melting curves that reveal highly temperature-dependent zones in which affinity binding (36-45 °C) or dissociation (25-33 °C and 50-65 °C) occurs. Additionally, temperature-dependent binding isotherms were constructed; from these, thermodynamic quantities involved in binding were extracted. The results illustrated a strong change in heat capacity of interaction for this system, suggesting a considerable thermodynamic influence controlling vasopressin-spiegelmer interaction.
The article is published online in Biomicrofluidics and is free to access.