"Method-specific" stability of serum C-peptide in a multicenter clinical study.

A Central laboratory that participates in multicenter clinical studies must consider and study the parameters that condition the in vitro stability of the analytes. We evaluated the effect of temperature on serum C-peptide storage during transport from clinical research centers to the Central laboratory. In particular, the stability for storage lengths from 0 to 24-48 hours at temperatures of between -20 degrees C and +37 degrees C were studied: the C-peptide assay was performed by means of a chemiluminescence and a RIA method.