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Vitamins D and A can be successfully measured by LC-MS/MS in cord blood diluted plasma

journal contribution
posted on 2015-11-01, 00:00 authored by A A Albarhani, Fiona Collier, R F Greaves, A L Ponsonby, K J Allen, Peter VuillerminPeter Vuillermin, P Roche, M W Clarke
OBJECTIVES: In widely used protocols for the collection and isolation of cord blood mononuclear cells, investigators are left with substantial volumes of diluted plasma which could be used for other measurements. The aim of this study was to ascertain the validity of umbilical cord blood (UCB) diluted plasma samples for vitamin D, A and E analysis compared to UCB serum samples. DESIGN & METHODS: Twenty UCB matched samples of diluted plasma and serum were collected. The samples were analysed by two liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods on two separate occasions. RESULTS: The results of 25(OH)D3 obtained by the two laboratories demonstrated close agreement with a mean difference of 0.14nmol/L [95% confidence interval (95% CI), -6.8 to 7.1]. Both methods demonstrate close agreement for 25(OH)D3 in UCB serum versus diluted UCB plasma; mean difference 2.2nmol/L [95% CI, -9.5 to 13.9] and 4.1nmol/L [95% CI, -14.5 to 6.1] for the results from Lab A and Lab B, respectively. Vitamin A was quantified by Lab A in UCB serum and diluted UCB plasma; mean difference 0.07μmol/L [95% CI, -0.41 to 0.28]. Results of 25(OH)D3 epimer and vitamin E in the diluted UCB plasma were below the limit of quantification, and could not be compared with UCB serum. CONCLUSIONS: Diluted UCB plasma can be used for the quantification of retinol and 25(OH)D3 by LC-MS/MS. By contrast, quantification of 25(OH)D3 epimer and vitamin E in diluted UCB plasma is not supported by this study due to limitations in analytical sensitivity.

History

Journal

Clinical biochemistry

Volume

48

Issue

16-17

Pagination

1105 - 1112

Publisher

Elsevier

Location

Amsterdam, The Netherlands

ISSN

1873-2933

eISSN

1873-2933

Language

eng

Publication classification

C Journal article; C1 Refereed article in a scholarly journal

Copyright notice

2015, Elsevier