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Concurrent liquid-chromatographic assay of retinol, alpha-tocopherol, beta-carotene, alpha-carotene, lycopene, and beta-cryptoxanthin in plasma, with tocopherol acetate as internal standard.
Abstract
A method is described for simultaneously determining retinol, alpha-tocopherol, beta-carotene, alpha-carotene, lycopene, and beta-cryptoxanthin in 0.25 mL of plasma. Plasma mixed with sodium dodecyl sulfate is deproteinized with ethanol containing tocopherol acetate, then extracted with heptane. The evaporated organic layer is reconstituted with mobile phase (methanol/acetonitrile/chloroform, 47/47/6 by vol) and injected onto a 100 x 4.6 mm 3-micron column of Spherisorb ODS-2 (LKB) at 1.5 mL/min. The alpha- and beta-carotenes are well resolved during the 6.5-min run. Retinol is monitored at 325 nm, the tocopherols at 292 nm, and the carotenoids at 450 nm. Extraction of concentrations as great as 135 mumol/L is complete. Intrabatch CVs were 1.7%, 2.3%, 4.1%, 10.4%, 6.4%, and 3.6% for retinol, alpha-tocopherol, beta-carotene, alpha-carotene, lycopene, and beta-cryptoxanthin, respectively. Interbatch CVs for measurements on 30 occasions over 11 weeks were about 10% for all components except alpha-tocopherol (5.3%). Results agree well with those for retinol, alpha-tocopherol, and beta-carotene in quality-control samples.
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Citations
Cited by
Bingham, S. (1997) · International Journal of Epidemiology · doi:10.1093/ije/26.suppl_1.s137 · Cited by 634
Gong, Y., Hounsa, A., Egal, S., Turner, P. C., Sutcliffe, A. E., Hall, A. J., Cardwell, K., & Wild, C. P. (2004) · Environmental Health Perspectives · doi:10.1289/ehp.6954 · Cited by 559
Bingham, S. A., Cassidy, A., Cole, T. J., Welch, A., Runswick, S. A., Black, A. E., Thurnham, D., Bates, C., Khaw, K. T., Key, T. J. A., et al. (1995) · British Journal of Nutrition · doi:10.1079/bjn19950057 · Cited by 377
Self-citationWiseman, H., O’Reilly, J. D., Adlercreutz, H., Mallet, A. I., Bowey, E. A., Rowland, I. R., & Sanders, T. A. (2000) · The American Journal of Clinical Nutrition · doi:10.1093/ajcn/72.2.395 · Cited by 377
Upritchard, J. E., Sutherland, W. H., & Mann, J. I. (2000) · Diabetes Care · doi:10.2337/diacare.23.6.733 · Cited by 353
Metadata
- Authors
- Thurnham, D. I., Smith, E., & Flora, P. S.
- Venue
- Clinical Chemistry
- Publisher
- Oxford University Press (OUP)
- Published
- 1988-02-01
- Volume
- 34
- Issue
- 2
- Pages
- 377-381
- ISSN
- 0009-9147 (ISSN-L)
- 1530-8561
- OpenAlex
- W2140673012
- Cited by
- 382
- References
- 0
- FWCI
- 5.17
- Type
- journal article
- Language
- en
- Open access
- closed
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- CoChat. (2026). Citation check: Concurrent liquid-chromatographic assay of retinol, alpha-tocopherol, beta-carotene, alpha-carotene, lycopene, and beta-cryptoxanthin in plasma, with tocopherol acetate as internal standard. https://app.cochat.ai/papers/10.1093/clinchem/34.2.377
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- Thurnham, D. I., Smith, E., & Flora, P. S. (1988). Concurrent liquid-chromatographic assay of retinol, alpha-tocopherol, beta-carotene, alpha-carotene, lycopene, and beta-cryptoxanthin in plasma, with tocopherol acetate as internal standard. Clinical Chemistry. https://doi.org/10.1093/clinchem/34.2.377
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
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