A method for the quantitative characterization of substances with regard to their properties of binding to amyloid-β (Aβ) conformers, comprising the steps of: —fractionating a sample including various Aβ conformers; —immobilizing a biotinylated Aβ conformer of the desired fraction on the surface of a substrate having high affinity for biotin; and —deriving the binding behavior of an aggregate quality control probe to the desired Aβ conformer from the measurement signal by determining the kinetic and/or thermodynamic parameters. A device for carrying out the method.