@article{discovery10129328, note = {This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made}, title = {Seven day pre-analytical stability of serum and plasma neurofilament light chain.}, number = {1}, journal = {Scientific Reports}, volume = {11}, month = {May}, year = {2021}, url = {https://doi.org/10.1038/s41598-021-90639-z}, author = {Altmann, P and Ponleitner, M and Rommer, PS and Haslacher, H and Mucher, P and Leutmezer, F and Petzold, A and Wotawa, C and Lanzenberger, R and Berger, T and Zetterberg, H and Bsteh, G}, abstract = {Neurofilament light chain (NfL) has emerged as a biomarker of neuroaxonal damage in several neurologic conditions. With increasing availability of fourth-generation immunoassays detecting NfL in blood, aspects of pre-analytical stability of this biomarker remain unanswered. This study investigated NfL concentrations in serum and plasma samples of 32 patients with neurological diagnoses using state of the art Simoa technology. We tested the effect of delayed freezing of up to 7 days and statistically determined stability and validity of measured concentrations. We found concentrations of NfL in serum and plasma to remain stable at room temperature when processing of samples is delayed up to 7 days (serum: mean absolute difference 0.9 pg/mL, intraindividual variation 1.2\%; plasma: mean absolute difference 0.5 pg/mL, intraindividual variation 1.3\%). Consistency of these results was nearly perfect for serum and excellent for plasma (intraclass correlation coefficients 0.99 and 0.94, respectively). In conclusion, the soluble serum and plasma NfL concentration remains stable when unprocessed blood samples are stored up to 7 days at room temperature. This information is essential for ensuring reliable study protocols, for example, when shipment of fresh samples is needed.} }