title: Spectra Library: An Assumption-Free In Situ Method to Access the Kinetics of Catechols Binding to Colloidal ZnO Quantum Dots.
abstract: Assumption-free and in situ resolving of the kinetics of ligand binding to colloidal nanoparticles (NPs) with high time resolution is still a challenge in NP research. A unique concept of using spectra library and stopped-flow together with a "search best-match" Matlab algorithm to access the kinetics of ligand binding in colloidal systems is reported. Instead of deconvoluting superimposed spectra using assumptions, species absorbance contributions (ligand@ZnO NPs and ligand in solution) are obtained by offline experiments. Therefrom, a library of well-defined targets with known ligand distribution between particle surface and solution is created. Finally, the evolution of bound ligand is derived by comparing in situ spectra recorded by stopped-flow and the library spectra with the algorithm. Our concept is a widely applicable strategy for kinetic studies of ligand adsorption to colloidal NPs and a big step towards deep understanding of surface functionalization kinetics.
authors.affiliation: Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstrasse 4, 91058, Erlangen, Germany.
authors.forename: Wei
authors.initials: W
authors.lastname: Lin
authors.affiliation: Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstrasse 4, 91058, Erlangen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Haderlein
authors.affiliation: Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstrasse 4, 91058, Erlangen, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Walter
authors.affiliation: Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstrasse 4, 91058, Erlangen, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Peukert
authors.affiliation: Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstrasse 4, 91058, Erlangen, Germany. doris.segets@fau.de.
authors.forename: Doris
authors.identifier: http://orcid.org/0000-0003-3102-2934
authors.initials: D
authors.lastname: Segets
keywords: colloids; kinetics; ligand exchange; nanoparticles; surface analysis