Determination of the abundance and isotope composition of nitrogen within organic compounds: a sealed tube technique for use with static vacuum mass spectrometers

A technique for the determination of the abundance and isotopic composition of nitrogen within organic compounds is described. It is intended for use with high-sensitivity static vacuum mass spectrometers. The accuracy of the abundance determination is +or-5% by weight and replicate delta 15 N determinations of nitrogen for five organic compounds were all within +or-8%. The compounds selected contained nitrogen within a variety of organic structures and with different types of nitrogen bonding including -NO 2 , -NH 2 , C identical to N, C=N, and C-N. In no case were detectable amounts of nitrogen oxides formed during oxidation. Blank analyses suggest that meaningful N abundance and delta 15 N determinations can be performed on materials containing greater than 20 ppm nitrogen by weight.