Characterisation of the 1H and 13C NMR spectra of N-acetylaspartylglutamate and its detection in urine from patients with Canavan disease

1H and 13C NMR spectra of N-acetylaspartylglutamate (NAAG) have been recorded and interpreted. The values of the 1H chemical shifts and 1H-(1)H coupling constants at different pH were obtained by iterative computer fitting of 1-D 1H NMR spectra. This provided information on the solution conformation of the investigated molecule. Proton-decoupled high resolution 13C NMR spectra of NAAG have been measured in a series of dilute water solution of various acidity. These data have provided a basis for unequivocal determination of the presence of NAAG in the urine sample of a patient suffering from Canavan disease. NMR spectroscopy provides a possibility of detecting NAAG in body fluids.