Materials with known ¹⁵N/¹⁴N isotopic composition

IAEA-310, ¹⁵N labelled urea

Unit Size: 2 x 0.1g
Price per Unit: 130 €
Report: NAHRES-5
Date of Release: 1989
Reference Sheet (pdf)

Reference material IAEA-310 consists of two materials (A and B) which were prepared from highly enriched ¹⁵N labelled urea by dilution with the unlabelled compound in redistilled water. After mixing, evaporation, freeze drying, crystallization and further mixing, the material was dispensed into glass vials. The values listed above were established on the basis of statistically valid results submitted by laboratories which had participated in an international intercomparison exercise organized by the Section of Nutritional and Health Related Environmental Studies [1].

Analyte	Value	Unit		N	R/I/C
δ15N (Vial A)	47.2	‰air N2	46.0 - 48.5	24	R
δ15N (Vial B)	244.6	‰air N2	243.9 - 245.4	23	R

[1] The isotopic compositions are given in parts per thousand difference from isotope ratio standard atmospheric N₂ (Air)
(N) Number of accepted laboratory means which were used to calculate the recommended or information values and their respective confidence intervals about the mean value
(R/I) Classification assigned to the property value for analyte (Recommended/Information)

References:

1. Parr R.M., Clements S.A. (1991): Intercomparison of enriched stable isotope reference materials for medical and biological studies, IAEA Report NAHRES-5, International Atomic Energy Agency, 31 pp.