Molecules, Vol. 25, Pages 1193: Chemometric Analysis of Low-field 1H NMR Spectra for Unveiling Adulteration of Slimming Dietary Supplements by Pharmaceutical Compounds

Molecules, Vol. 25, Pages 1193: Chemometric Analysis of Low-field 1H NMR Spectra for Unveiling Adulteration of Slimming Dietary Supplements by Pharmaceutical Compounds Molecules doi: 10.3390/molecules25051193 Authors: Nao Wu Stéphane Balayssac Saïda Danoun Myriam Malet-Martino Véronique Gilard The recent introduction of compact or low-field (LF) NMR spectrometers that use permanent magnets, giving rise to proton (1H) NMR frequencies between 40 and 80 MHz, have opened up new areas of application. The two main limitations of the technique are its insensitivity and poor spectral resolution. However, this study demonstrates that the chemometric treatment of LF 1H NMR spectral data is suitable for unveiling medicines as adulterants of slimming dietary supplements (DS). To this aim, 66 DS were analyzed with LF 1H NMR after quick and easy sample preparation. A first PLS-DA model built with the LF 1H NMR spectra from forty DS belonging to two classes of weight-loss DS (non-adulterated, and sibutramine or phenolphthalein-adulterated) led to the classification of 13 newly purchased test samples as natural, adulterated or borderline. This classification was further refined when the model was made from the same 40 DS now considered as representing three classes of DS (non-adulterated, sibutramine-adulterated, and phenolphthalein-adulterated). The adulterant (sibutramine or phenolphthalein) was correctly predicted as confirmed by the examination of the 1H NMR spectra. A...
Source: Molecules - Category: Chemistry Authors: Tags: Communication Source Type: research