Surface enhanced resonance Raman spectroscopy of dyes: semi-quantitative trace analysis
Shadi, Iqbal Tahear (2005) Surface enhanced resonance Raman spectroscopy of dyes: semi-quantitative trace analysis. PhD thesis, University of Greenwich.Full text not available from this repository.
Herein analysis of dye molecules has been carried out by means of surface enhanced Raman spectroscopy (SERS) and/or surface enhanced resonance Raman spectroscopy (SERRS) using citrate- and/or borohydride-reduced silver colloids employing laser exciting wavelengths equal to 514.5 and/or 632.8 nm. SERS and/or SERRS spectra are reported using, as model system probes, eight dye molecules which belong to several distinct chemical structural classes. Experimental protocols were developed and subsequently modified, as required, for each dye molecule examined. Vibrational spectroscopic profiles were obtained, where possible, with respect to concentration and pH dependence. SERS and/or SERRS vibrational bands provided unique fingerprint spectra for each dye molecule.
In an attempt to develop novel applications of SERRS the technique has been used, in a kinetic investigation, to monitor and analyse the synthesis of the dye indigo carmine from indigo using a silver sol as the SERRS substrate/medium. In another study it was possible to differentiate between two structurally similar anthraquinones, alizarin and purpurin, using SERRS. It was also possible to demonstrate the existence of multiple molecular species of certain dye molecules, as a function of pH e.g. nuclear fast red, metanil yellow, purpurin and alizarin. For some dye molecules e.g. alcian blue it was possible to combine the linear regions of normal (non-resonance/non-enhanced) Raman and SERS/SERRS plots, thereby extending the dynamic range available for semi-quantitative analysis. The sensitivity of the SERS/SERRS technique for semi-quantitative trace analysis of eight dye molecules has been successfully demonstrated.
|Item Type:||Thesis (PhD)|
|Uncontrolled Keywords:||surface enhanced Raman spectroscopy, chemical analysis, dye molecules,|
|Subjects:||Q Science > QC Physics|
|School / Department / Research Groups:||School of Science|
School of Science > Department of Pharmaceutical, Chemical & Environmental Sciences
|Last Modified:||12 Apr 2012 14:26|
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