Objectives: To evaluate the effect of a freeze-thaw cycle on β-trace protein (βTP) and β2-microglobulin (β2M).
Design and methods: We compared βTP and β2M concentrations before and after a single freeze-thaw cycle in long-term stored samples from 172 participants of the Third National Health and Nutrition Examination Survey (NHANES III).
Results: Measurements of βTP and β2M before and after freeze-thaw were highly correlated with Spearman's coefficients of 0.90 and 0.99, respectively. Serum concentrations of βTP were slightly lower after freeze-thaw (-0.05 mg/L, P=0.006). Measurements of β2M did not differ before and after freeze-thaw (P=0.35).
Conclusions: βTP and β2M measurements were robust to a single freeze-thaw cycle, although β2M appeared more stable than βTP. These results have implications for future studies of these biomarkers.
Copyright © 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.