Insulin measurements in haemolysed serum: influence of insulinase inhibitors.

Author(s): Sapin R, Ongagna JC, Gasser F, Grucker D

Publication: Clin Chim Acta, 1998, Vol. 274, Page 111-7

PubMed ID: 9681602 PubMed Review Paper? No

Purpose of Paper

Conclusion of Paper

Studies

1. Study Purpose

   The purpose of this study was to determine the effects of hemolysis, storage temperature and duration, and addition of CMPS on insulin levels in EDTA-K3 plasma and serum. Hemolysed specimens were prepared by adding hemolysate to plasma and serum.

   Summary of Findings:

   When non-hemolyzed plasma was stored at 4 degrees C for up to 24 hours, a 5% decrease in insulin was found, which the authors noted as relatively stable, but when specimens were stored at room temperature for 1 day, an 8.7% decrease in insulin was found. Addition of the inhibitor CMPS to specimens stored at room temperature stabilized insulin levels after storage for 24 h (-5.4%). Increasing hemolysis resulted in increased measurement of plasma insulin by radioimmunoassay (RIA), but storage at room temperature decreased plasma insulin. In hemolysed plasma and serum, insulin detection by the immunoradiometric assay (IRMA) rose with increasing hemolysis. However, when hemolyzed plasma was stored at room temperature, insulin measured by IRMA decreased by 27% after 2 h and 98% after 24 h, however, when stored for 24 h at 4 degrees C insulin decreased by 26%. Adding CMPS to hemolyzed plasma specimens attenuated the effects of hemolysis and storage.

   Biospecimens

   • Bodily Fluid - Serum
   • Bodily Fluid - Plasma

   Preservative Types

   • None (Fresh)

   Diagnoses:

   • Not specified

   Platform:

   Analyte	Technology Platform
   Protein	Immunoradiometric assay
   Protein	Radioimmunoassay

   Pre-analytical Factors:

   Classification	Pre-analytical Factor	Value(s)
   Biospecimen Aliquots and Components	Blood and blood products	Plasma Serum
   Storage	Storage temperature	4 degrees C Room temperature
   Storage	Storage duration	0 h 2 h 3 h 18 h 24 h
   Analyte Extraction and Purification	Protease inhibitor	No protease inhibitor added p-chloromercuriphenyl sulfonate sodium salt
   Biospecimen Aliquots and Components	Hemolysis	Freeze/thaw-induced Hemolysate added No hemolysate added

   View more