title: Spectrometer calibration protocol for Raman spectra recorded with different excitation wavelengths.
abstract: The combination of Raman spectroscopy with chemometrics has gained significant importance within the last years to address a broad variety of biomedical and life science questions. However, the routine application of chemometric models to analyze Raman spectra recorded with Raman devices different from the device used to establish the model is extremely challenging due to Raman device specific influences on the recorded Raman spectra. Here we report on the influence of different non-resonant excitation wavelengths on Raman spectra and propose a calibration routine, which corrects for the main part of the spectral differences between Raman spectra recorded with different (non-resonant) excitation wavelengths. The calibration routine introduced within this contribution is an improvement to the known 'standard' calibration routines and is a starting point for the development of a calibration protocol to generate spectrometer independent Raman spectra. The presented routine ensures that a chemometric model utilizes only Raman information of the sample and not artifacts from small shifts in the excitation wavelength. This is crucial for the application of Raman-spectroscopy in real-world-settings, such as diagnostics of diseases or identification of bacteria.
authors.affiliation: Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller-University, Helmholtzweg 4, 07743 Jena, Germany; Leibniz Institute of Photonic Technology, Albert Einstein Straße 7, 07745 Jena, Germany.
authors.forename: T W
authors.initials: TW
authors.lastname: Bocklitz
authors.affiliation: Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller-University, Helmholtzweg 4, 07743 Jena, Germany; Leibniz Institute of Photonic Technology, Albert Einstein Straße 7, 07745 Jena, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Dörfer
authors.affiliation: Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller-University, Helmholtzweg 4, 07743 Jena, Germany; Leibniz Institute of Photonic Technology, Albert Einstein Straße 7, 07745 Jena, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Heinke
authors.affiliation: Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller-University, Helmholtzweg 4, 07743 Jena, Germany; Leibniz Institute of Photonic Technology, Albert Einstein Straße 7, 07745 Jena, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Schmitt
authors.affiliation: Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller-University, Helmholtzweg 4, 07743 Jena, Germany; Leibniz Institute of Photonic Technology, Albert Einstein Straße 7, 07745 Jena, Germany. Electronic address: juergen.popp@uni-jena.de.
authors.forename: J
authors.initials: J
authors.lastname: Popp
mesh_terms: D002138:Calibration; D016002:Discriminant Analysis; D055620:Optical Phenomena; D013059:Spectrum Analysis, Raman
keywords: Chemometric analysis; Raman spectroscopy; Spectrometer calibration