Pre-analytical stability of serum biomarkers for neurological disease: Neurofilament-light, glial fibrillary acidic protein and contactin-1

Zoë Y. G. J. van Lierop, Inge M. W. Verberk, Kees W. J. van Uffelen, Marleen J. A. Koel-Simmelink, Lisanne in't Veld, Joep Killestein, Charlotte E. Teunissen

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21 Citations (Scopus)


Objectives: Neurofilament-light (NfL), glial fibrillary acidic protein (GFAP) and contactin-1 (CNTN1) are blood-based biomarkers that could contribute to monitoring and prediction of disease and treatment outcomes in neurological diseases. Pre-analytical sample handling might affect results, which could be disease-dependent. We tested common handling variations in serum of volunteers as well as in a defined group of patients with multiple sclerosis (pwMS). Methods: Sample sets from 5 pwMS and 5 volunteers at the outpatient clinic were collected per experiment. We investigated the effect of the following variables: collection tube type, delayed centrifugation, centrifugation temperature, delayed storage after centrifugation and freeze-thawing. NfL and GFAP were measured by Simoa and CNTN1 by Luminex. A median recovery of 90-110% was considered stable. Results: For most pre-analytical variables, serum NfL and CNTN1 levels remained unaffected. In the total group, NfL levels increased (121%) after 6 h of delay at 2-8 °C until centrifugation, while no significant changes were observed after 24 h delay at room temperature (RT). In pwMS specifically, CNTN1 levels increased from additional freeze-thaw cycles number 2 to 4 (111%-141%), whereas volunteer levels remained stable. GFAP showed good stability for all pre-analytical variables. Conclusions: Overall, the serum biomarkers tested were relatively unaffected by variations in sample handling. For serum NfL, we recommend storage at RT before centrifugation at 2-8 °C up to 6 h or at RT up to 24 h. For serum CNTN1, we advise a maximum of two freeze-thaw cycles. Our results confirm and expand on recently launched consensus standardized operating procedures.

Original languageEnglish
Pages (from-to)842-850
Number of pages9
JournalClinical chemistry and laboratory medicine
Issue number6
Early online date2022
Publication statusPublished - 1 May 2022


  • biomarkers
  • immunoassay
  • nervous system diseases
  • pre-analytical phase

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