Direct analytical sample quality assessment for biomarker investigation: Qualifying cerebrospinal fluid samples

Measurement of biochemical markers represents an important aid to clinicians in the earlydiagnosis and prognosis of neurological diseases. Many factors can contribute to increase thechances that a biomarker study becomes successful. In a cerebrospinal fluid analysis (CSF),more than 84% of laboratory errors can be attributed to several preanalytical variables thatinclude CSF collection, storage, and freeze thawing cycles. In this concept paper, we focus onsome critical issues arising from basic proteomics investigation in order to highlight somekey elements of CSF quality control. Furthermore, we propose a direct assessment of samplequality (DASQ) by applying a fast MALDI-TOF-MS methodology to evaluate molecular featuresof sample degradation and oxidation. We propose DASQ as a fast and simple initial step to beincluded in large-scale projects for neurological biomarker studies. In fact, such a procedurewill improved the development of standardized protocols in order to have well-characterizedCSF biobanks.