Quantification of protein-ligand dissociation kinetics in heterogeneous affinity assays

Research output: Contribution to journalArticleAcademicpeer-review

19 Citations (Scopus)
2 Downloads (Pure)


Biochemical affinity assays inherently involve interactions of heterogeneous nature. We report a methodology to discriminate between and accurately characterize specific and nonspecific interactions in force-induced dissociation assays. Ligand-coupled superparamagnetic particles are incubated on surfaces coated with a mixture of specific receptors and nonspecifically interacting proteins. Consequently, a mixed population of surface bound particles is formed with different binding natures. Magnetic field gradients are used to apply translational forces on the bound particles. Using a multicomponent dissociation analysis, we are able to make a distinction between weak nonspecific interactions, strong nonspecific interactions, and specific interactions. We validate the model by comprehensive experiments in which the biochemical components and applied forces are varied. The low-force data yield reliable values for the spontaneous dissociation rates of single-molecule specific bonds, and at high forces, the bond barriers are modified by the applied force. The results generate a new perspective for applications of magnetic force affinity assays in studies of heterogeneous molecular biorecognition.
Original languageEnglish
Pages (from-to)9287-9294
Number of pages8
JournalAnalytical Chemistry
Issue number21
Publication statusPublished - 2012


Dive into the research topics of 'Quantification of protein-ligand dissociation kinetics in heterogeneous affinity assays'. Together they form a unique fingerprint.

Cite this