title: New ultrarapid-scanning interferometer for FT-IR spectroscopy with microsecond time-resolution.
abstract: A novel Fourier-transform infrared (FT-IR) rapid-scan spectrometer has been developed (patent pending EP14194520.4) which yields 1000 times higher time resolution as compared to conventional rapid-scanning spectrometers. The central element to achieve faster scanning rates is based on a sonotrode whose front face represents the movable mirror of the interferometer. A prototype spectrometer with a time resolution of 13 μs was realized, capable of fully automated long-term measurements with a flow cell for liquid samples, here a photosynthetic membrane protein in solution. The performance of this novel spectrometer is demonstrated by recording the photoreaction of bacteriorhodopsin initiated by a short laser pulse that is synchronized to the data recording. The resulting data are critically compared to those obtained by step-scan spectroscopy and demonstrate the relevance of performing experiments on proteins in solution. The spectrometer allows for future investigations of fast, non-repetitive processes, whose investigation is challenging to step-scan FT-IR spectroscopy.
authors.affiliation: Department of Physics, Experimental Molecular Biophysics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Süss
authors.affiliation: Institute for Crystal Growth, Max-Born Straße 2, 12489 Berlin, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Ringleb
authors.affiliation: Department of Physics, Experimental Molecular Biophysics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Heberle