Concepts and recent advances in microchip electrophoresis coupled to mass spectrometry: Technologies and applications

Abstract

The online coupling of microchip electrophoresis (ME) as a fast, highly efficient, and low-cost miniaturized separation technique to mass spectrometry (MS) as an information-rich and sensitive characterization technique results in ME-MS an attractive tool for various applications. In this paper, we review the basic concepts and latest advances in technology for ME coupled to MS during the period of 2016-2021, covering microchip materials, structures, fabrication techniques, and interfacing to electrospray ionization (ESI)-MS and matrix-assisted laser desorption/ionization-MS. Two critical issues in coupling ME and ESI-MS include the electrical connection used to define the electrophoretic field strength along the separation channel and the generation of the electrospray for MS detection, as well as, a miniaturized ESI-tip. The recent commercialization of ME-MS in zone electrophoresis and isoelectric focusing modes has led to the widespread application of these techniques in academia and industry. Here we summarize recent applications of ME-MS for the separation and detection of antibodies, proteins, peptides, carbohydrates, metabolites, and so on. Throughout the paper these applications are discussed in the context of benefits and limitations of ME-MS in comparison to alternative techniques.

An electrochemical device to control sample pH locally in Lab-on-PCB devices: An investigation into spatial resolution

“…The PCB was designed to slot into a 64 pin PCIE connector which was mounted into a breakout board for easy control over multiple pads in the array. A holder was designed to create a uniform well (Colyer et al, 1997;Cui et al, 2005;Mohamadi et al, 2007;Peng et al, 2008;Dutta, 2019;Yu et al, 2019;Niu et al, 2021;Naghdi et al, 2022).…”

Capillary electrophoresis‐mass spectrometry for intact protein analysis: Pharmaceutical and biomedical applications (2018–March 2023)

“…The offline approach with MALDI-MS is utilized rarely. For more information about mCE coupled with MS, the reader is referred to the recent reviews [14,[29][30][31].…”

“…The specific class is represented by microfabricated CE devices (microchips) with integrated spray emitters. A detailed discussion of most of the microchip CE‐MS interfacing is summarized in a recent review [31].…”

“…Continuous advancement of CE has been focused on overcoming key obstacles, such as low concentration sensitivity and strong capillary wall adsorption of proteins, which could be particularly problematic when employed to analyze complex biological samples. Microchip CE (mCE) is also a trending technology thanks to its short analysis time, high throughput and sensitivity, and very low sample consumption [14,[29][30][31].…”

Strategies for capillary electrophoresis: Method development and validation for pharmaceutical and biological applications—Updated and completely revised edition

“…In their review, they outline the analytics of biopharmaceuticals such as monoclonal antibodies (mAbs), antibody-drug conjugates (ADCs), fusion proteins, growth factors, cytokines, nucleic acids, and viral vectors, particularly related to the characterization of quality attributes. The review by Lechner et al discusses state-of-the-art analysis of mAbs and ADCs [177] and additional reports [178][179][180][181][182][183] are discussed in other sections of this review. The application of CE in the pharmaceutical industry, related to the analysis and characterization of therapeutic proteins, is well described by Kaur et al [184].…”