1. A new integrated TLC/MU-ATR/SERS advanced approach for the identification of trace amounts of dyes in mixtures
- Author
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Silvia Prati, Irene Bonacini, Giorgia Sciutto, Moreno Meneghetti, Rocco Mazzeo, Lucio Litti, Sciutto, Giorgia, Prati, Silvia, Bonacini, Irene, Litti, L., Meneghetti, M., and Mazzeo, Rocco
- Subjects
Enhanced vibrational techniques ,Analytical chemistry ,02 engineering and technology ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,symbols.namesake ,chemistry.chemical_compound ,Dyes ,MU/ATR ,SERS ,Environmental Chemistry ,Spectroscopy ,Fourier transform infrared spectroscopy ,Dyes, Enhanced vibrational techniques, MU/ATR, SERS ,Elution ,010401 analytical chemistry ,Silver iodide ,021001 nanoscience & nanotechnology ,Thin-layer chromatography ,0104 chemical sciences ,chemistry ,Attenuated total reflection ,symbols ,Dyeing ,0210 nano-technology ,Raman spectroscopy - Abstract
The present research is focused on the setting up of an advanced analytical system for the detection of synthetic dyes. The system is based on the combination of an innovative thin layer chromatography (TLC) plate coupled with enhanced infrared (MU-ATR, metal underlayer attenuated total reflection) and Surface Enhanced Raman (SERS) spectroscopy. In particular, a TLC plate made of silver iodide (AgI) applied onto a gold coated glass slide (AgI@Au) is proposed as an efficient stationary phase for the separation of dyes mixtures. The separated dyes are then identified by means of both enhanced FTIR and SERS, performed directly on the same eluted spots. The use of a mid-IR transparent inorganic salt as stationary phase coupled with the underneath gold layer avoids spectral interferences, enhancing the signal obtained from ATR analyses. At the same time, SERS spectra can be recorded as the TLC plate may act as a SERS active substrate due to the photoreduction of AgI to metallic Ag caused by the exposure to the laser during the Raman analysis. Different mixtures of synthetic dyes of known composition, widely used in dyeing processes, have been tested and the method resulted to be effective in identifying trace amounts in the order of tens nanograms. Moreover, the method has been further evaluated on a real case study represented by dyes extracted from dyed wool.
- Published
- 2017