NBS22 is a secondary reference material. Its intended use is as calibrant when δ13C and δ2H are determined in organic materials using IRMS (Isotope Ratio Mass Spectrometry) coupled with an EA (Elemental Analyser) and Pyrolizer, for obtaining traceability of the data to the VPDB δ13C scale and VSMOW-SLAP δ2H scale, respectively. NBS 22 was prepared by S. Silverman, Chevron Oil Company, La Habra, California [1]. Details about the characterization of NBS22 are reported in [2] and [3].
Stable isotope ratio | Reference value | Combined standard uncertainty with k=1 |
δ13CVPDB (‰) | -30.03 | 0.04 |
δ2HVSMOW-SLAP (‰) | -117.2 | 0.6 |
References:
- SILVERMAN, S.R., "Investigations of petroleum origin and evolution mechanisms by carbon isotope studies", Isotopic and Cosmic Chemistry (CRAIG, H., MILLER, S.L., WASSERBURG, G.J., Eds.), North Holland, (1964) 92-102.
- COPLEN, T.B., BRAND, W.A., GEHRE, M., GRÖNING M., MEIJER, H.A.J., TOMAN, B., VERKOUTEREN, R.M., New Guidelines for 13C Measurements, Anal. Chem. 78 7 (2006) 2439-2441.
- SCHIMMELMANN, A., QI H., COPLEN, T.B., BRANDT, W.A., FONG, J., MEIER-AUGENSTEIN, W., KEMP, H.F., TOMAN, B., ACKERMANN, A., ASSONOV, S., AERTS-BIJMA, A.T., BREICHA, R., CHIKARAISHI, Y., DARWISH, T., ELSNER, M., GEHRE, M., GEILMANN, H., GROENING, M., HELIE, J.F., HERRERO-MARTIN, S., MEIJER, H.A.J., SAUER, P.E., SESSION A.L., WERNEN R.A. Organic Reference Materials for Hydrogen, Carbon, and Nitrogen Stable Isotope-Ratio Measurements: Caffeines, n‑Alkanes, Fatty Acid Methyl Esters, Glycines, L‑Valines, Polyethylenes, and Oils. Anal. Chem. 88 (2016) 4294−4302