Immunoaffinity capillary electrophoresis as a powerful strategy for the quantification of low‐abundance biomarkers, drugs, and metabolites in biological matrices

Abstract

In the last few years, there has been a greater appreciation by the scientific community of how separation science has contributed to the advancement of biomedical research. Despite past contributions in facilitating several biomedical breakthroughs, separation sciences still urgently need the development of improved methods for the separation and detection of biological and chemical substances. In particular, the challenging task of quantifying small molecules and biomolecules, found in low abundance in complex matrices (e.g., serum), is a particular area in need of new highefficiency techniques. The tandem or on-line coupling of highly selective antibody capture agents with the high-resolving power of CE is being recognized as a powerful analytical tool for the enrichment and quantification of ultra-low abundance analytes in complex matrices. This development will have a significant impact on the identification and characterization of many putative biomarkers and on biomedical research in general. Immunoaffinity CE (IACE) technology is rapidly emerging as the most promising method for the analysis of low-abundance biomarkers; its power comes from a three-step procedure: (i) bioselective adsorption and (ii) subsequent recovery of compounds from an immobilized affinity ligand followed by (iii) separation of the enriched compounds. This technology is highly suited to automation and can be engineered to as a multiplex instrument capable of routinely performing hundreds of assays per day. Furthermore, a significant enhancement in sensitivity can be achieved for the purified and enriched affinity targeted analytes. Thus, a compound that exists in a complex biological matrix at a concentration far below its LOD is easily brought to well within its range of quantification. The present review summarizes several applications of IACE, as well as a chronological description of the improvements made in the fabrication of the analyte concentrator-microreactor device leading to the development of a multidimensional biomarker analyzer.

Bioanalytical Methods for Food Allergy Diagnosis, Allergen Detection and New Allergen Discovery

“…As a hybrid technique combining the immunoaffinity extraction of the sample with its electrophoretic separation, IACE is a powerful tool for the analysis of the complex biological samples [54]. For the total IgE quantification by IACE-LIF, magnetic beads, coated with antihuman IgE antibodies, were first trapped inside the separation capillary using two permanents magnets.…”

Current trends in sample preparation for growth promoter and veterinary drug residue analysis

“…A number of good review papers have been published on immunoaffinity chromatography (IAC) and should be consulted for a more detailed overview of this topic [116][117][118][119][120][121] …”

Confirmation of immuno‐reactivity of the recombinant major birch pollen allergen Bet v 1a by affinity‐CIEF

“…radioallergosorbent test [21,22], enzyme allergosorbent test [23], ELISA [7,20], or microarrays [14,24]. These tests immobilize either the polyclonal antibodies (Ab) yielded from blood samples or the target Ags on a solid support and capture related Ags or specific antibodies, respectively [25][26][27][28]. Visualization is done with labeled secondary antibodies [20,28].…”