The present paper aims to find a method of comprehensive characterisation and definition of
complex mixtures. For this purpose the technique of spectral fingerprint shows most advantages.
It has been applied to the definition of very similar herbal antitussic preparations containing an
extract from the plantain plant (Plantago lanceolata). The synchronous fluorescent spectrum (Dl =
15 nm), in contrast to the classic emission spectrum, can resolve the individual preparations. The
complete characteristic of the preparation is, however, provided only by the method of a special
fluorescent fingerprint, which developed from a combination of the technique of recording synchro-
nous spectra with a programmably changeable difference in Dl and the computer processing of
graphic records in the form of contour maps. The combination makes it possible to graphically define
and characterise complex mixtures, the exact composition of which may not be even known. The
method can be used in the analysis of pharmaceutical, food, cosmetic and other products, in the
control of their quality, observance of the technological process, in the comparison of identical
products by different manufacturers as well as in revealing counterfeit brand products. Spectral
fluorescent fingerprints – contour fluorescent maps can be stored in a database and they posses the
same informational value as fingerprints in criminological practice.
synchronous spectrum – fluorescent fingerprint – contour maps –