RESUMO
BACKGROUND: Circulating microRNA (miRNA) biomarkers have attracted attention as possible blood-based indicators of disease. However, pre-analytic technical issues including serum preparation remain problematic for the clinical translation of such technology. This study investigated the effect of decreased sample preparation time on miRNA measurement. METHODS: Blood samples obtained from healthy donors were drawn into blood collection tubes with or without clot activator, and sera were obtained at different preparation time points. The expression levels of miR16 and miR21 were examined. RESULTS: The miR-16 expression levels were significantly higher in sera separated after 5 minutes compared to ones separated after 10 and 60 minutes, whereas no significant difference of miR21 expression was detected in association with the serum separation conditions. CONCLUSIONS: Serum miRNA expression levels should be interpreted carefully with consideration of the characteristics of collection tubes and clotting status of serum separation.