Ligand/receptor binding kinetics on planar surfaces are often Studied using surface plasmon resonance (SPR) but the range of measurable intrinsic sorption constants and surface capacities for macromolecules is limited by slow diffusive mass transport. This study examines stimulating transverse hydrodynamic diffusion as a new method to increase the range of measurable intrinsic rate constants or surface capacities. Expressions and operating conditions are developed which show that the new method can measure rate constants and surface capacities >= 10-fold higher than the existing capabilities. These developments are illustrated by identifying conditions to measure rapid adsorption rates of Adenovirus Type 5 and cytochrorne c, respectively, on high-capacity planar surfaces and sorptive spheres. (c) 2005 Elsevier Ltd. All rights reserved.