This poster from Durham University demonstrates how Flow Induced Dispersion Analysis (FIDA) was used to measure the binding of the RNA-modifying enzyme PUS7 to tRNA, tracking hydrodynamic radius and fluorescence changes as enzyme concentration increased. FIDA showed a 1:1 interaction at low-nanomolar affinity, complementing evidence that PUS7 pseudouridylates multiple tRNA species and shapes stem-cell homeostasis. It is an example of using FIDA to characterise protein–RNA binding affinity and stoichiometry in solution.