Designed Fluorescence Data

This data is made from known analytes. They can be used for second order calibration tests, and for other concepts of interest to test on a fluorescence data set. It can easily be divided into smaller units if the user so desires. The samples were generated and measured by Åsmund Rinnan (KVL, DK) and Jordi Riu (Universitat Rovira i Virgili, Spain).

Get the data (28 MB)

The data are available in the data set format defined by the Dataset Object freely available at www. eigenvector.com and also part of the PLS_Toolbox, and was made in Matlab version 6.5. If you do not have the Dataset Object or PLS toolbox, the data will simply be in a structure format. There are two structures. One with the EEMs, the other with the concentration profiles. Download the data and write “load fluordata” in MATLAB. If you use the data we would appreciate that you report the results to us as a courtesy of the work involved in producing and preparing the data. Also you may want to refer to the data by referring to

  1. Rinnan, Å.: Application of PARAFAC on Spectral Data, 2004, PhD thesis, Royal Veterinary and Agricultural University (DK)
  2. Bro, R, Rinnan, Å, Faber, K.: Standard Error of Prediction for Multilinear PLS. 2. Practical Implementation in Fluorescence Spectroscopy, Chemometrics and Intelligent Laboratory Systems, 2004, Accepted

 

Data

There are a total of six different fluorophores in the dataset: catechol, hydroquinone, indole, resorcinol, tryptohpane and tyrosine. These were chosen on the basis of closeness to the 1st order Rayleigh scatter line and their overlap in both emission and excitation spectra. In total 405 samples are recorded.

Figure 1: The pure excitation and emission spectra for the six analytes.

Out of these six analytes, 12 datasets where measured (see Table 1). All of the datasets are more or less equal, only with small differences among them, described in the column to the right. An ‘x’ in columns 2-7 indicates if the fluorophore is present or not in the dataset.

Table 1: A short description of the 12 datasets.

DatasetFluorophoresDescription
CatecholHydroquinoneIndoleResorcinolTryptophaneTyrosine
0xxxxxxPure standards
1   xxxTyrosine kept constant, while factorial design on Resorcinol and Tryptophane
2xxxxxxAll samples have 2 or 3 fluorophores
3xxx x Catechol and Hydroquinone vary equally
4xxx xxAll samples have 2 or 3 fluorophores
5x  x  Test of Catechol and Resorcinol
6xxx xxAll samples have 3 or 4 fluorophores
7xxx xxLow concentrations
8xxx  x 
9xxx  xCatechol concentration slightly lower than previous max (possible non-linear on the previous maximum concentration level)
10xxx xxAll samples have 2 or 3 fluorophores
11xxx  xReplicate of dataset 8 and 9

 

Instrumentation

The instrument used for the analysis was a Varian Eclipse Fluorescence Spectrometer. The instrument setup was optimized to give satisfying resolution within a limited time. It took roughly 12 minutes per sample (including all the sub-sampling). In Table 2below, the instrument setup is shown. Sub-samples state that the sample was left in the instrument and scanned five consecutive times. Every measurement consists of 136 emission wavelengths × 19 excitation wavelengths.

Table 2: Instrument setup

Instrument settingsValue
Slit width5 nm (both Emission and Excitation)
Excitation230-320 (nm) – Every 5 nm, Highest wavelength first
Emission230-500 (nm) – Every 2 nm
Scan rate1920 nm/min
PMT Detector voltage600V
Sub-samples5

 

General note

In seems that Catechol contains some impurities, and thus gives rise to an extra component in the data sets where it is present.