00353 857087743
French flag access to spectrochrom

Chromatographic Fingerprints comparison

You can see below 2 chromatograms of the same fragrance, controlled several months after (bottom) the first control (top). It shows a shifting of all the peaks:

two chromatograms to compare

A 3 minutes shift is visible on the last peaks due to the ageing of the column.
Despite this non-linear shifting, GC-LC CONCORDANCE software is able to detect similarities and differences between these two chromatograms with 192 peaks and provides a report with the differences between these two chromatograms. Both red marks in the window show the non concordance between the two products – Coumarine in the standard and allyl cyclohexyl propionate in the sample.

chromatograms comparisons graphics screen

The report (short mode) shows only differences between these two chromatograms with only peaks > 0.1% as set in the settings as well as differences out of the tolerances defined in the settings.

E.g. here for peaks between:

– 0.1 and 1%, the difference of tolerance is set to 40%

– 1% and 10%, tolerance is set to 15%

– 10% and 100%, tolerance is set to 3%

chromatograms comparisons simple report

Upon repeating analysis, retention time differences of components will vary from seconds to minutes. Moreover, if the analyzed product has hundreds of components separated by a few seconds on the chromatogram, the manual identification is long, difficult and is subject to human error.

Today even if a gas chromatograph has all the new electronic regulation developments of temperature and gas flow rates, it is unable to balance these complex variations.

An automatic and accurate analysis is now possible with GC-LC CONCORDANCE!


Chromatographic fingerprint comparisons is now possible in an automatic, fast, reliable and precise way with GC-LC CONCORDANCE. Chemists, you are now free from the laborious visual control of all peaks of your chromatograms and can then concentrate on the relevant analysis of the differences of your products.

See below the curves of automatic compensation of the not linear shifting of compounds (3 minutes on the last peaks!), after mathematical treatment.

Equation and curve for non-linear RT shifting