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Products Facts - Xtricator

Resolving Multicomponent Data into Spectra and Chromatograms
Xtricator is a software package for quantitative and qualitative analysis of data from analytical instruments like HPLC-DAD, GC-IR, GC-MS, LC-MS, FTIR, excitation-emission spectroscopy, etc.
Xtricator contains procedures for:
  • Pre-processing and pre-screening of the data
  • Background correction
  • Determination of multivariate decision limits
  • Assessment of number of analytes in various regions of the multicomponent profile
  • Resolution of the multicomponent profile into analytical profiles (chromatograms and spectra) of the contributing analytes using both Direct and Iterative methods.
  • Calculation of concentrations
  • Comparing of profiles extracted using different procedures

Background Correction and Data Pre-processing

Included in Xtricator are routines for correction of baseline drift and offset as well as systematic spectral backgrounds. Data with heteroscedastic noise (noise dependent upon signal level) can be transformed to homoscedastic noise (noise independent upon signal level). Xtricator offers you sophisticated ways of detecting baseline drift and offset. ·
  • Detection by means of LPG ·
  • Detection by means of ETA

A latent-projective graph (LPG) is a tool used to detect selective regions and background.

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Determination of Decision Limit

A multivariate decision limit is determined from the data - not by any a priori assumption of the system behaviour. In this way, we account for the fact that the decision limit for an analyte depends both on the other coexisting analytes, and the specific noise behaviour of the instrument. Xtricator also supports a Wavelet based dynamic decision limit.

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Rank Mapping

To analyse multicomponent systems it is necessary to determine the chemical rank (number of analytes) in the different regions of the data table. The rank mapping procedure in Xtricator is called ETA (Eigenstructure Tracking Analysis). ETA is a "moving window of evolving size" technique. This map displays the information about the number of analytes in different data regions. The information in the rank map is subsequently used in the resolution process, where every analyte's analytical profiles are calculated. The ETA plot is a very important visual tool in Xtricator.

Rank map

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Resolution into Spectra and Chromatograms

Xtricator supports two different kinds of resolution approaches, Direct and Iterative methods.
Iterative methods:
  • Gentle
  • Alternating Regression
Direct methods:
The three main methods included in Xtricator are:
  • Heuristic Evolving Latent Projections (HELP)
  • Orthogonal Projections (OP)
  • Sequential Rank Analysis (SERA)

These methods again consist of several techniques performing different tasks, eg. Principal Components Analysis (PCA) and Evolving Factor Analysis (EFA).

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Correlation Chromatography

It is sometimes interesting to investigate the correlation between a selective region (e.g., a pure peak) and all other parts of the data. Correlation chromatography is designed for this purpose. This technique uses correlation coefficients to assess the degree of similarities. A correlation coefficient near 1.0 indicates that the test compound contributes to the investigated area, while a coefficient near 0.0 indicates regions with chemical analytes that are very different from the tested one

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Interacting with Other Software Packages

Files can be imported from and exported to various formats, such as ASCII, Excel, Lotus, JCAMP, and CDF. Other instrument formats can be implemented on request. Both resolved chromatograms and spectra can be exported and plots can be placed on the clipboard and pasted into other software packages like Word, AmiPro, etc. Plots can be copied as bitmaps and metafiles

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Required Hardware and Software

*PC (Pentium II or higher) running Windows 95, Windows NT or higher
*32 MB of memory
*16 MB of free hard-disk space

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