Immunoaffinity capillary electrophoresis for the analysis of biomarkers in blood

VIZIOLI, NM

Alcalá de Henares

Simposio; 25th Latin-American Symposium on Biotechnology, Biomedical, Biopharmaceutical, and Industrial Applications of Capillary Electrophoresis and Microchip Technology-LACE 2019; 2019

Improving the detection capabilities of low abundance proteins and correlating translational and post-translational modifications in proteins with their function are main goals in bioanalytical chemistry [1]. In that sense, immunoaffinity capillary electrophoresis comes to provide the advantages of the high affinity of antibodies fixed on a solid support and the high resolution of capillary electrophoresis [2]. Such devices cannot only be used for concentration enrichment, isolation, or extraction of proteins but also to achieve microreactions, allowing the on-line analysis of reaction products. The antibodies can be immobilized directly on a portion of the inner surface of the capillary wall, a membrane, beads, monolithic structures, or even a multibore capillary. In comparison with off-line solid phase extraction techniques, immunoaffinity capillary electrophoresis requires lower sample volume, and only a few microliters of organic solvent or buffers are consumed. The entire process is carried out in the CE instrument and a small quantity of sorbent material is needed, which makes on-line preconcentraction cheaper than the off-line one. In addition, sensitivity in CE is increased at least 100-fold, allowing the detection of analytes from 1 ng/mL with UV absorbance detector to 1 pg/mL with a LIF detector, and even femtograms per milliliter. The potential of immunoaffinity capillary electrophoresis will be demonstrated through its application to quantify specific protein level in blood.