Role of non-fluorescent chromophores in inner filter effect correction and PARAFAC decomposition

Elfrida Mihaela Carstea (1) , Stéphane Mounier (2) , Roland Redon (2) , Cristina L. Popa (3)

1 INOE - National Institute of Research and Development for Optoelectronics
2 PROTEE - Processus de Transfert et d'Echanges dans l'Environnement - EA 3819
3 National Institute of Materials Physics

Numerous studies have shown the impact of inner filter effect (IFE) on the fluorescence signal. IFE reduces the fluorescence intensity and distorts the fluorescence peak shape and position, through the absorption of the emitted radiation by the sample components. In this study, we aimed to understand the role of a non-fluorescing chromophore in IFE correction and PARAFAC decomposition. Solutions of three fluorophores, tryptophan, fluorescein and quinine sulfate, and an absorbing compound, green ink, have been prepared using the controlled dilution approach (CDA). PARAFAC identified three components associated with quinine sulfate, fluorescein and an IFE artifact, which was caused by a shift in peak position. Results showed that the absorption of the chromophore plays an important role in component determination. We observed that the CDA-PARAFAC was able to correct the quinine sulfate and fluorescein signals, and to suppress the IFE artifact component. However, the method was not effective in removing the IFE impact at high concentrations. The results have significant implications on the analysis of samples that contain complex mixtures of fluorophores and chromophores, such as colored natural organic matter or nutrients, like NO 3 2- .

Mots clés: Inner filter effect; fluorescence spectroscopy; controlled dilution approach; PARAFAC

Domaines: Chimie théorique et/ou physique; Chimie analytique

Elfrida Mihaela Carstea, Stéphane Mounier, Roland Redon, Cristina L. Popa. Role of non-fluorescent chromophores in inner filter effect correction and PARAFAC decomposition. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy [1994-..], 2019, pp.117878. ⟨10.1016/j.saa.2019.117878⟩. ⟨hal-02398690⟩