Direct measurement of sorption on three-dimensional surfaces such as resins, membranes or other preformed materials using lateral dispersion to estimate rapid sorption kinetics or high binding capacities

摘要

Described are methods allowing measurement of adsorption and desorption of analytes with membranes or resins directly using surface plasmon resonance (SPR). Also described are methods for assembling intact resins or membranes on SPR surfaces. Such methods provide estimates of mass-action ion-exchange adsorption and desorption rates accounting for steric (σ) and characteristic charge (ν) effects. The methods further permit accurate estimation of rate constants for uniform adsorption of a homogeneous analyte solution on homogeneous adsorptive sites distributed heterogeneously in space, relative to the planar boundary. Solutions are obtained for locally porous media and solid spheres. The methods are extendible to other media and heterogeneous adsorptive sites. The methods further provide for enhancement of lateral mass transport in such optical measurement instruments through radial hydrodynamic diffusion (radial dispersion) by, for example, incorporating porous media in flow cells of detection devices such as, but not limited to, SPR or TIRF instruments.