title: Simultaneous Identification of Neutral and Anionic Species in Complex Mixtures without Separation.
abstract: A chemosensory system is reported that operates without the need for separation techniques and is capable of identifying anions and structurally similar bioactive molecules. In this strategy, the coordination of analytes to a metal complex with an open binding cleft generates "static structures" on the NMR timescale. Unique signals are created by strategically placing fluorine atoms in close proximity to bound analytes so that small structural differences induce distinct (19)F NMR shifts that can be used to identify each analyte. The utility of this method is illustrated by quantifying caffeine levels in coffee, by identifying ingredients in tea and energy drinks, and by discriminating between multiple biogenic amines with remote structural differences six carbon atoms away from the binding site. We further demonstrate the simultaneous identification of multiple neutral and anionic species in a complex mixture.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA.
authors.forename: Yanchuan
authors.identifier: http://orcid.org/0000-0002-2903-4218
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA.
authors.forename: Lily
authors.identifier: http://orcid.org/0000-0001-7960-4699
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA. tswager@mit.edu.
authors.forename: Timothy M
authors.identifier: http://orcid.org/0000-0002-3577-0510
authors.initials: TM
authors.lastname: Swager
mesh_terms: D000838:Anions / Q000032:analysis*; D045424:Complex Mixtures / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy
chemical_list: D000838:Anions; D045424:Complex Mixtures
keywords: N ligands; NMR spectroscopy; chemosensors; fluorine; palladium; pincer complexes