title: Leveraging bimodal kinetics to improve detection specificity.
abstract: Optical microcavities are high sensitivity transducers able to detect single nanoparticles and molecules. However, the specificity of detection is dependent on the availability of an appropriate targeting moiety with minimal cross-reactivity. In the present work, an alternative approach is shown. Namely, using biotin-functionalized toroidal microcavities, the dissociation constant of biotin to two different streptavidin complexes (free and polystyrene bead) is determined. Based on the difference in affinity and in mass transport, the two complexes are identified from a mixture. By leveraging information in the binding site, improved specificity can be achieved.
authors.affiliation: Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089, USA.
authors.forename: C
authors.initials: C
authors.lastname: Shi
authors.forename: S
authors.initials: S
authors.lastname: Mehrabani
authors.forename: A M
authors.initials: AM
authors.lastname: Armani
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D001710:Biotin / Q000378:metabolism; D007700:Kinetics; D008863:Microspheres; D055096:Optical Devices; D011137:Polystyrenes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D019809:Streptavidin / Q000737:chemistry / Q000378:metabolism; D013499:Surface Properties
chemical_list: D011137:Polystyrenes; D001710:Biotin; D012822:Silicon Dioxide; D019809:Streptavidin