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Analyte stability during the total testing process: studies of vitamins A, D and E by LC-MS/MS

  • Ali A. Albahrani , Victor Rotarou , Peter J. Roche and Ronda F. Greaves EMAIL logo
Published/Copyright: April 12, 2016
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Clinical Chemistry and Laboratory Medicine (CCLM)
From the journal Clinical Chemistry and Laboratory Medicine (CCLM) Volume 54 Issue 10

Abstract

Background:

There are limited evidence based studies demonstrating the stability of fat-soluble vitamins (FSV) measured in blood. This study aimed to examine the effects of light, temperature and time on vitamins A, D and E throughout the total testing process.

Methods:

Four experiments were conducted. Three investigated the sample matrix, of whole blood, serum and the extracted sample, against the variables of temperature and light; and the fourth experiment investigated the sample during the extraction process against the variable of light. All samples were analysed via our simultaneous FSV method using liquid chromatography-tandem mass spectrometry technology. The allowable clinical percentage change was calculated based on biological variation and desirable method imprecision for each analyte. The total change limit was ±7.3% for 25-OH-vitamin D3, ±11.8% for retinol and ±10.8% for α-tocopherol.

Results:

Vitamins D and E were stable in the investigated conditions (concentration changes <4%) in the pre-analytical and analytical stages. Vitamin A showed photosensitivity in times >48 h with concentration changes of −6.8% (blood) and −6.5% (serum), both are within the allowable clinical percentage change. By contrast, the extracted retinol sample demonstrated a concentration change of −18.4% after 48 h of light exposure. However, vitamin A in the serum and extracted solution was stable for one month when stored at −20°C.

Conclusions:

Blood samples for vitamins D and E analyses can be processed in normal laboratory conditions of lighting and temperature. The required conditions for vitamin A analysis are similar when performed within 48 h. For longer-term storage, serum and vitamin A extracts should be stored at −20°C.

Keywords: LC-MS/MS; light; 25-OH-vitamin D3; retinol; α-tocopherol

Acknowledgments:

The work performed at RMIT University was conducted in the RMIT-Agilent Clinical Biochemistry Mass Spectrometry Collaboration Laboratory. We wish to thank Mrs Annabel Mitchell and Dr. Chris Fouracre from Agilent Technologies for their input into the method development.

  1. Author contributions: All authors contributed equally to the development and analysis of this study. Dr. Ali Albahrani conducted the experiments in the clinical biochemistry laboratories, RMIT University, and he wrote the first draft of the manuscript. All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: This work was part of Dr. Ali A. Albahrani’s PhD project which was supported in kind by Agilent Technologies as part of the RMIT Clinical Biochemistry – Agilent Mass Spectrometry Collaboration.

  3. Employment or leadership: None declared.

  4. Honorarium: None declared.

  5. Competing interests: The funding organisation(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.

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Supplemental Material:

The online version of this article (DOI: 10.1515/cclm-2015-1034) offers supplementary material, available to authorized users.

Received: 2015-10-23
Accepted: 2016-2-15
Published Online: 2016-4-12
Published in Print: 2016-10-1

©2016 Walter de Gruyter GmbH, Berlin/Boston

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https://doi.org/10.1515/cclm-2015-1034
Keywords for this article
LC-MS/MS; light; 25-OH-vitamin D3; retinol; α-tocopherol

Articles in the same Issue

  1. Frontmatter
  2. Editorial
  3. Serum myoglobin immunoassays: obsolete or still clinically useful?
  4. Reviews
  5. Kounis syndrome: an update on epidemiology, pathogenesis, diagnosis and therapeutic management
  6. What do we know about homocysteine and exercise? A review from the literature
  7. Mini Review
  8. Osteocalcin as a potential risk biomarker for cardiovascular and metabolic diseases
  9. Opinion Paper
  10. Statistical approach for optimization of external quality assurance (EQA) studies of molecular and serological viral diagnostics
  11. EFLM Article
  12. Sample collections from healthy volunteers for biological variation estimates’ update: a new project undertaken by the Working Group on Biological Variation established by the European Federation of Clinical Chemistry and Laboratory Medicine
  13. General Clinical Chemistry and Laboratory Medicine
  14. Analyte stability during the total testing process: studies of vitamins A, D and E by LC-MS/MS
  15. Improvement in the predictive ability of the Intermountain Mortality Risk Score by adding routinely collected laboratory tests such as albumin, bilirubin, and white cell differential count
  16. Cystatin C provides a better estimate of the effect of glomerular filtration rate on serum human epididymis protein 4 concentrations
  17. Verification of the harmonization of human epididymis protein 4 assays
  18. Clinical utility of urinary liver-type fatty acid binding protein measured by latex-enhanced turbidimetric immunoassay in chronic kidney disease
  19. Comparison of three analytical platforms for quantification of the neurofilament light chain in blood samples: ELISA, electrochemiluminescence immunoassay and Simoa
  20. Reference Values and Biological Variations
  21. Distribution of antiphospholipid antibodies in a large population-based German cohort
  22. Cardiovascular Diseases
  23. Serum protein S100 as marker of postoperative delirium after off-pump coronary artery bypass surgery: secondary analysis of two prospective randomized controlled trials
  24. Infectious Diseases
  25. Copeptin predicts 10-year all-cause mortality in community patients: a 10-year prospective cohort study
  26. Clinical and laboratory findings in the diagnosis of right lower quadrant abdominal pain: outcome analysis of the APPAC trial
  27. Letters to the Editor
  28. Why a new algorithm using high-sensitivity cardiac troponins for the rapid rule-out of NSTEMI is not adapted to routine practice
  29. Optimal collection tubes for plasma glucose determination: confusion reigns supreme
  30. Long-term stability of serum samples positive for carbohydrate deficient transferrin (CDT) routinely stored at −20 °C
  31. Seasonal variations in plasma free metanephrine concentrations are not evident in the West of Ireland
  32. Potential errors in the determination of urinary ammonium by formol titration
  33. Interference by biological anti-cancer drugs in electrophoretic and immunofixation techniques
  34. A point mutation in the thiopurine S-methyltransferase gene that led to exon 5 deletion in the transcribed mRNA
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