Capillary electrophoresis‐based immunoassays: Principles and quantitative applications

Abstract

The use of capillary electrophoresis as a tool to conduct immunoassays has been an area of increasing interest over the last decade. This approach combines the efficiency, small sample requirements, and relatively high speed of CE with the selectivity of antibodies as binding agents. This review examines the various assay formats and detection modes that have been reported for these assays, along with some representative applications. Most CE immunoassays in the past have employed homogeneous methods in which the sample and reagents are allowed to react in solution. These homogeneous methods have been conducted as both competitive binding immunoassays and as non-competitive binding immunoassays. Fluorescent labels are most commonly used for detection in these assays, but enzyme labels have also been utilized for such work. Some additional work has been performed in CE immunoassays with heterogeneous methods in which either antibodies or an analog of the analyte is immobilized to a solid support. These heterogeneous methods can be used for the selective isolation of analytes prior to their separation by CE or to remove a given species from a sample/reagent mixture prior to analysis by CE. These CE immunoassays can be used with a variety of detection modes, such as fluorescence, UV/visible absorbance, chemiluminescence, electrochemical measurements, mass spectrometry, and surface plasmon resonance.

Electrophoretic mobility measurements of fluorescent dyes using on‐chip capillary electrophoresis

“…Most relevant here, they are frequently used as markers or labels in a wide variety of electrophoresis techniques including isoelectric focusing (IEF) [5,6], capillary zone electrophoresis (CZE) [7,8] and isotachophoresis (ITP) [9,10]. The latter techniques rely on electromigration, so accurate characterization of ion electrophoretic mobility is essential.…”

Immunoaffinity Chromatography: A Review

“…In recent years, IAC has been integrated with other analytical methods such as CE and MS. CE immunoassays (where antibodies are immobilized in CE capillaries) are utilized because they are easily automated, require small amounts of sample and reagents and still maintain a good detection limit, and offer relatively fast separation (Moser & Hage, 2008;Phillips and Wellner, 2007). …”

Quantitative study of stereospecific binding of monoclonal antibody to anti-benzo(a)pyrene diol epoxide-N2-dG adducts by capillary electrophoresis immunoassay

“…As B binds independently to P 1 and P 2 , the binding constants (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) and (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15) can be obtained: …”

“…(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) shows that Eq. (3-17) is consistent with the definition of binding constant of B and P 1 , as shown in the Eq.…”