, Volume 30, Issue 6, pp 394–396 | Cite as

Haemolysis affects insulin but not C-peptide immunoassay

  • S. O'Rahilly
  • M. A. Burnett
  • R. F. Smith
  • J. H. Darley
  • R. C. Turner


Venous blood was taken at the end of a glucose infusion test in 19 individuals and divided into four aliquots, 3 of which were variably haemolysed by repeated passage through a 23-gauge needle to simulate traumatic venepuncture. Plasma insulin (measured by both a charcoal separation and a double-antibody method), C-peptide, and haemoglobin were measured in each aliquot, and haemolysis was also assessed visibly. A significant loss of immuno-assayable plasma insulin was found in samples with only a trace of visible haemolysis, with up to 90% lost in severely haemolysed samples. Plasma C-peptide was unaffected by haemolysis. This represents an additional advantage for the use of plasma C-peptide in assessing insulin secretion.

Key words

Insulin C-peptide radio-immunoassay haemolysis 


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Copyright information

© Springer-Verlag 1987

Authors and Affiliations

  • S. O'Rahilly
    • 1
  • M. A. Burnett
    • 1
  • R. F. Smith
    • 2
  • J. H. Darley
    • 3
  • R. C. Turner
    • 1
  1. 1.Diabetes Research LaboratoriesJohn Radcliffe HospitalOxfordUK
  2. 2.Sheikh Rashid Diabetes UnitJohn Radcliffe HospitalOxfordUK
  3. 3.Department of HaematologyJohn Radcliffe HospitalOxfordUK

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