Application of Multivariate Curve Resolution–Alternate Least Square Technique on Extracting Pure Spectral Components from Multiple Emitting Systems: a Case Study
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Multiple emitting components in a fluorophoric system often produce complicated emission spectra. Extracting the individual spectral information from the composite spectra is important in order to comprehend the photophysical processes occurring in the multifluorophoric systems. Although the combination of Principal Component Analysis and Multivariate Curve Resolution-Alternate Least Square (PCA/MCR-ALS) technique is a well-known approach for curve deconvolution, its applicability in the spectral deconvolution of vibronically and electronically mixed up emitting systems as well as systems merged up with multiple electronic bands without a priori knowledge of the individual emitting species, is not properly studied. The present work highlights the strength of PCA/MCR-ALS in retrieving pure spectral information from the set of complex spectra arising out of the regular variation of causative factors that result in the variation of spectral composition. The retrieval of the emission bands utilizing the PCA/MCR-ALS technique has been made without having a priori information of the emitting species present in the multifluorophoric systems and the resolved spectra correspond well with the fluorescence spectra of the individual chemical species. The common curve fitting methods such as Gaussian and Lorentzian techniques have been found to be unsuccessful in providing meaningful photophysical information through the retrieved spectra. A comparative study of the curve fitting techniques MCR-ALS, Gaussian and Lorentzian in a set of complicated emission spectra of (i) pyrene and its excimer, (ii) pyrene and its excimer in presence of benzo[a]pyrene, and (iii) fisetin in bile salt medium is presented herein in details.
KeywordsFluorescence MCR-ALS Gaussian Lorentzian Excimer ESPT
Madhumita Tarai is thankful to the Council of Scientific and Industrial Research (CSIR) New Delhi, India for providing a research fellowship. The authors thank CSIR for financial support to carry out the work.
- 3.Blass WE (1981) Deconvolution of absorption spectra. University of Tennessee, Academic Press Inc., New YorkGoogle Scholar
- 7.Meira M, Quintella CM, Ribeiro EM de O, Silva WL (2015) Gaussian fit to the fluorescence spectra for determination of adulteration to diesel by addition of residual oil. Biomass Conv Bioref 5: 295–297Google Scholar
- 8.Lancaster P, Šalkauskas K (1986) Curve and surface fitting: an introduction. Academic Press, LondonGoogle Scholar
- 12.Lerner PB, Chadwick MB, Sokolov IM (1993) Inhomogeneous broadening of electronic transitions in liquid helium bubble: the role of shape fluctuations. J Chem Phys 90:319–330Google Scholar
- 20.Ruckebusch C (2016) Resolving spectral mixtures: with applications from ultrafast time-resolved spectroscopy to super-resolution imaging. 30. Elsevier, AmsterdamGoogle Scholar
- 23.Kumar K, Mishra AK (2012) Application of ‘multivariate curve resolution alternating least square (MCR–ALS)’ analysis to extract pure component synchronous fluorescence spectra at various wavelength offsets from total synchronous fluorescence spectroscopy (TSFS) dataset of dilute aqueous solutions of fluorophores. Chemom Intell Lab 116: 78–86CrossRefGoogle Scholar
- 27.Ghose A, Rebarz M, Maltsev OV, Hintermann L, Ruckebusch C, Fron E, Hofkens J, Mely Y, Naumov P, Sliwa M, Didier P (2014) Emission properties of oxyluciferin and its derivatives in water: revealing the nature of the emissive species in firefly bioluminescence. J Phys Chem B 119: 2638–2649CrossRefPubMedGoogle Scholar
- 29.Wise BM, Gallagher NB, Shaver JM, Windig W, Koch RS, Bro R (2006) PLS_Toolbox 4.0 Eigen vector research. The Math Works, NatickGoogle Scholar
- 31.Turro NJ, Kuo P (1968) Pyrene excimer formation in micelles of nonionic detergents and of water-soluble polymers. Langmuir 4:438–442Google Scholar
- 35.Pisarčik M, Devinsky F, Pupak M (2015) Determination of micelle aggregation numbers of alkyltrimethyl ammonium bromide and sodium dodecyl sulfate surfactants using time-resolved fluorescence quenching. De Gruyter Open 13: 922–931Google Scholar