Identification of specific pre-analytical quality control markers in plasma and serum samples

Blood is a liquid connective tissue with a complex composition that supplies oxygen and nutrients to cells. It is minimally invasive to obtain and can be used in "omics" technologies. Current research regarding blood-based biomarkers has gained considerable attention as a useful tool for diagnostic, therapeutic, and drug development; however, several research groups have reported controversial results despite using the same analytical platform. Such discrepancy can be caused by errors made during the pre-analytical phase. Therefore, quality control of pre-analytical variables is an important factor that could affect the reproducibility and credibility of results. This review discusses the challenge to identify blood quality control markers and describes several molecules that could be potential candidates.