To obtain serum, ablood sample is allowed to clot (coagulation). The sample is thencentrifuged to remove the clot and blood cells, and the resulting liquidsupernatant is serum.[3]
Blood serum and plasma are some of the largest sources ofbiomarkers, whether for diagnostics or therapeutics. Its vast dynamic range, further complicated by the presence of lipids, salts, and post-translational modifications, as well as multiple mechanisms of degradation, presents challenges in analytical reproducibility, sensitivity, resolution, and potential efficacy. For analysis of biomarkers in blood serum samples, it is possible to do a pre-separation byfree-flow electrophoresis that usually consists of a depletion of serumalbumin protein.[6] This method enables greater penetration of the proteome via separation of a wide variety of charged or chargeable analytes, ranging from small molecules to cells.[citation needed]
Like many othermass nouns, the wordserum can be pluralized when used in certainsenses. To speak of multiple serum specimens from multiple people (each with a unique population of antibodies), physicians sometimes speak ofsera (the Latin plural, as opposed toserums).[citation needed] Etymologically serum is derived from the Proto-Indo-European *ser- ("to flow, run").
^Nissum M, Foucher AL (August 2008). "Analysis of human plasma proteins: a focus on sample collection and separation using free-flow electrophoresis".Expert Review of Proteomics.5 (4):571–87.doi:10.1586/14789450.5.4.571.PMID18761468.S2CID207200988.