Study on the decomposition of the amadori compoundN-(1-deoxy-D-fructos-1-y1)-glycine in model systems: Quantification by fast atom bombardment tandem mass spectrometry

A new method for the quantification of N-(1-deoxy-D-fructos-1-yl)-glycine (DFG) was developed based on isotope dilution fast atom bombardment tandem mass spectrometry using 13C-labelled DFG as an internal standard. This method, which requires neither derivatization nor clean-up of the samples, was used to study the degradation of DFG under different conditions (time and pH). It was found that the decomposition of DFG at 90°C was favoured at pH 7 compared to pH 6. The higher stability of DFG at pH 6 was due to 1,2-enolization leading to the relatively stable 3-deoxglucosone.