Analyzing Binding Kinetics: Which Method Is Best for Your Next SPR Experiment? Application note

The study of biomolecular interactions is critical to our understanding of biological systems and the forces involved in driving biological action. Biomolecular interaction analysis (BIA) enables us to examine how specific biomolecules interact, providing us with important information about their mechanism and behaviour in living systems. With the versatility to be applied on many biomolecular pair types, including antigens and antibodies, drugs and proteins, and hormones and receptors, BIA has been an accelerator of many discoveries in medical, pharmaceutical and fundamental biological research.  

Among the parameters that can be measured, kinetic analysis is a powerful method for elucidating the rate at which an interaction occurs. Observing how quickly a biomolecular complex forms and comes apart, or the association and dissociation rates of the interaction, can give insights about the roles of different biomolecules, residence times for antibody and receptor-target complexes, competitor drugs’ mechanisms, and much more.

Tools such as surface plasmon resonance (SPR) have advanced our ability to perform kinetic studies by measuring interactions in real-time and in a label-free environment. In an SPR experiment, there are two common experimental methods for kinetic analysis: Multi-cycle kinetics and single-cycle kinetics. Before selecting a format for your next experiment, it is important to understand how they differ and which is best for your specific interaction.