MULTIELEMENT AND MULTISITE ISOTOPIC ANALYSIS OF NICOTINE FROM TOBACCO-LEAVES

The carbon, nitrogen and hydrogen stable-isotope contents of nicotine extracted from tobacco leaves were determined by Isotope Ratio Mass Sp ectrometry (overall H-2, C-13 and N-15 contents) and by the SNIF-NMR m ethod (site-specific deuterium content). In addition, nicotine was che mically degraded into nicotinic acid so that the intramolecular distri bution of carbon and nitrogen isotopes could be studied, A prerequisit e for reliable measurements is the use of experimental procedures free of isotopic fractionation. Therefore, it was ensured that isotopic in tegrity was maintained throughout extraction, purification and chemica l degradation steps. The multi-element and multi-site information prov ided is tentatively interpreted in terms of biochemical isotopic effec ts on intramolecular distribution patterns and of the influence of env ironmental factors on nicotine isotopic parameters.