title: Communication: Probing the absolute configuration of chiral molecules at aqueous interfaces.
abstract: We demonstrate that the enantiomers of chiral macromolecules at an aqueous interface can be distinguished with monolayer sensitivity using heterodyne-detected vibrational sum-frequency generation (VSFG). We perform VSFG spectroscopy with a polarization combination that selectively probes chiral molecular structures. By using frequencies far detuned from electronic resonances, we probe the chiral macromolecular structures with high surface specificity. The phase of the sum-frequency light generated by the chiral molecules is determined using heterodyne detection. With this approach, we can distinguish right-handed and left-handed helical peptides at a water-air interface. We thus show that heterodyne-detected VSFG is sensitive to the absolute configuration of complex, interfacial macromolecules and has the potential to determine the absolute configuration of enantiomers at interfaces.
authors.affiliation: FOM Institute for Atomic and Molecular Physics, Science Park 104, 1098 XG Amsterdam, The Netherlands.
authors.forename: Stephan
authors.initials: S
authors.lastname: Lotze
authors.affiliation: FOM Institute for Atomic and Molecular Physics, Science Park 104, 1098 XG Amsterdam, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Versluis
authors.affiliation: Laboratory of Macromolecular and Organic Chemistry, Department of Chemical Engineering and Chemistry, and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
authors.forename: Luuk L C
authors.initials: LL
authors.lastname: Olijve
authors.affiliation: Laboratory of Macromolecular and Organic Chemistry, Department of Chemical Engineering and Chemistry, and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
authors.forename: Luuk
authors.initials: L
authors.lastname: van Schijndel
authors.affiliation: Laboratory of Macromolecular and Organic Chemistry, Department of Chemical Engineering and Chemistry, and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
authors.forename: Lech G
authors.initials: LG
authors.lastname: Milroy
authors.affiliation: Laboratory of Macromolecular and Organic Chemistry, Department of Chemical Engineering and Chemistry, and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
authors.forename: Ilja K
authors.initials: IK
authors.lastname: Voets
authors.affiliation: FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.
authors.forename: Huib J
authors.initials: HJ
authors.lastname: Bakker
mesh_terms: D000388:Air; D000818:Animals; D004583:Electrons; D046911:Macromolecular Substances / Q000737:chemistry; D009842:Oligopeptides / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D014732:Vibration; D014867:Water / Q000737:chemistry*
chemical_list: C570180:AFP1 peptide, Trapa natans; D046911:Macromolecular Substances; D009842:Oligopeptides; D014867:Water