Capillary Electrophoresis Analysis of Prostate-Specific Antigen (PSA)
The Capillary Electrophoresis (CE) profile of isoforms (peaks) of a glycoprotein can be useful to show alterations in its posttranslational modifications (PTMs) linked to diseases. These changes can modify the electrophoretic mobility of these isoforms in a minor extent and, therefore, very reproducible CE methods are needed to detect them. In this chapter, a method for the analysis of prostate-specific antigen (PSA) by Capillary Zone Electrophoresis (CZE) with UV detection is detailed. High reproducibility in the separation of a large number of PSA isoforms is achieved by performing capillary conditioning in acid media and by using a background electrolyte (BGE) at pH 8.0 formulated with decamethonium bromide and urea.
Key wordsReproducibility Capillary conditioning Prostate-specific antigen PSA Isoform Proteoform Glycoform Cancer biomarker
Financial support from the Spanish Ministry of Economy and Competitiveness (project CTQ2013-43236-R) is acknowledged. Noemi Farina-Gomez and Monica Gonzalez acknowledge the Ph.D. JAE-pre grant and the JAE-doc grant, respectively, from CSIC, co-financed by the European Social Fund (ESF). Diana Navarro-Calderon acknowledges her contract in the frame of the Youth Guarantee Implementation Plans, financed by the ESF and the Youth Employment Initiative (YEI).
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