Recent developments and applications of capillary and microchip electrophoresis in proteomic and peptidomic analyses.

This review presents recent developments and applications of capillary and microchip electromigration methods in proteomics and peptidomics. Sample preparation methods as well as instrumental innovations in the coupling of these advanced electromigration methods with mass spectrometry detection employed in proteomic and peptidomic analyses are presented. Interesting applications of various capillary electromigration methods in bottom-up as well as top-down proteomics, including investigation of post-translational modifications of proteins are described. In addition, several examples of the use of capillary electromigration methods combined with mass spectrometry detection in clinical proteomics and peptidomics are demonstrated.

Recent applications of microchip electrophoresis to biomedical analysis.

Many separation methods have been developed for biomedical analysis, including chromatographic (e.g. high performance liquid chromatography (HPLC) and gas chromatography (GC)) and electrophoretic methods (e.g. gel electrophoresis and capillary electrophoresis (CE)). Among these techniques, CE provides advantages in terms of high separation efficiency, simplicity, low sample and solvent volume consumption, short analysis time and applicability to a wide range of biomedically important substances. Microchip electrophoresis (ME) is a miniaturized platform of CE and is now considered as a simpler and more convenient alternative, which has demonstrated potential in analytical chemistry. High-throughput, cost-effective and portable analysis systems can be developed using ME. The current review describes different separation modes and detectors that have been employed in ME to analyze various classes of biomedical analytes (e.g. pharmaceuticals and related substances, nucleic acids, amino acids, peptides, proteins, antibodies and antigens, carbohydrates, cells, cell components and lysates). Recent applications (during 2010-2014) in these areas are presented in tables and some significant findings are highlighted.

Present state of microchip electrophoresis: state of the art and routine applications.

Microchip electrophoresis (MCE) was one of the earliest applications of the micro-total analysis system (µ-TAS) concept, whose aim is to reduce analysis time and reagent and sample consumption while increasing throughput and portability by miniaturizing analytical laboratory procedures onto a microfluidic chip. More than two decades on, electrophoresis remains the most common separation technique used in microfluidic applications. MCE-based instruments have had some commercial success and have found application in many disciplines. This review will consider the present state of MCE including recent advances in technology and both novel and routine applications in the laboratory. We will also attempt to assess the impact of MCE in the scientific community and its prospects for the future.

Integrating amperometric detection with electrophoresis microchip devices for biochemical assays: recent developments.

Recent advances in microfluidic systems, particularly in the Micro Total Analysis System (µTAS) or Lab On a Chip (LOC), drive the current analysis tools and equipment towards miniaturization, rapid at-line testing and mobility. The state-of-the-art microfluidic technology targets a wider range but smaller volumes of analytes, making the analytical procedure relatively easier and faster. This trend together with faster electronics and modern instrumentation systems will make real-time and in situ analysis a definite possibility. This review focuses on microchip capillary electrophoresis with amperometric detection (MCE-AD) for the detection of DNA and other electroactive analytes. The problems associated with the microchip design, in particular the choice of materials and the configuration of electrodes are discussed thoroughly and solutions are proposed. Significant developments in the related areas are also covered and reviewed critically.

Recent progress in microchip electrophoresis-mass spectrometry.

This review highlights the methodological and instrumental developments in microchip electrophoresis (MCE)-mass spectrometry (MS) from 1997. In MCE-MS, the development of ionization interface is one of the most important issues to realize highly sensitive detection and high separation efficiency. Among several interfaces, electrospray ionization (ESI) has been mainly employed to MCE-MS since a simple structure of the ESI interface is suitable for coupling with the microchips. Although the number of publications is still limited, laser desorption ionization (LDI) interface has also been developed for MCE-MS. The characteristics of the ESI and LDI interfaces applied to the electrophoresis microchips are presented in this review. The scope of applications in MCE-MS covers mainly biogenic compounds such as bioactive amines, peptides, tryptic digests and proteins. This review provides a comprehensive table listing the applications in MCE-MS.

Recent developments in instrumentation for capillary electrophoresis and microchip-capillary electrophoresis.

Over the last years, there has been an explosion in the number of developments and applications of CE and microchip-CE. In part, this growth has been the direct consequence of recent developments in instrumentation associated with CE. This review, which is focused on the contributions published in the last 5 years, is intended to complement the articles presented in this special issue dedicated to instrumentation and to provide an overview of the general trends and some of the most remarkable developments published in the areas of high-voltage power supplies, detectors, auxiliary components, and compact systems. It also includes a few examples of alternative uses of and modifications to traditional CE instruments.

CEC: selected developments that caught my eye since the year 2000.

During the last decade, a number of new developments have emerged in the field of CEC. This paper focuses only on monolithic columns prepared from synthetic polymers. Monolithic columns have become a well-established format of stationary phases for CEC immediately after their inception in the mid-1990s. They are readily prepared in situ from liquid precursors. Also, the control over both porous properties and surface chemistries is easy to achieve. These advantages make the monolithic separation media an attractive alternative to capillary columns packed with particulate materials. Since the number of papers concerned with just this single topic of polymer-based monolithic CEC columns is large, this overview describes only those approaches this author found interesting.

Trends in CE-MS 2005-2006.

CE-MS has gained further attention as a multidimensional analytical approach. The number of publications dealing with this technique is still increasing on the level of application as well as method development-oriented approaches. Additionally, 15 reviews were published the last two years focusing on CE-MS. An overview of all papers found to have been published within 2005 and 2006 is given in tabulated form. Additionally, four promising technical trends are chosen to be presented in detail: (i) chip-based CE-MS, (ii) capillary coatings in CE-MS, (iii) new trends in CEC-MS and (iv) the application of 2-D CE-MS.

Recent advances in CE and CEC of pollutants.

Recent advances in CE and CEC separation, detection and sample preparation/preconcentration methodologies, for the determination of a variety of compounds having current or potential environmental relevance, have been overviewed. The reviewed literature has illustrated the wide range of CE applications available, indicating a continuing interest in CE and CEC in the environmental field. New developments in chip-based CE systems are also discussed.

Trends in analysis of explosives by microchip electrophoresis and conventional CE.

The continuous upsurge in terrorist activity has generated tremendous demand for innovative tools capable of detecting nitrated organic, inorganic, and peroxide-based explosives. This article directly extends the previous exhaustive review (Electrophoresis 2006, 27, 244-256) and overviews the research activity in the field of microchip and conventional capillary electrophoresis for analysis of a variety of explosive compounds and mixtures in the past two years (middle 2005-middle 2007), with the focus on world-to-chip interfaces and detection techniques.

Recent advances in sheathless interfacing of capillary electrophoresis and electrospray ionization mass spectrometry.

On line sheathless capillary electrophoresis (CE)-electrospray ionization (ESI) mass spectrometry is developing as a powerful method in bioanalytics as it provides high resolution, sensitivity, relatively short analysis times, and amenability to a wide class of compounds. However, unlike the popular nano liquid chromatography (nano LC) or sheath-flow CE/ESI-MS, the sheathless coupling lacks standardized designs and protocols. For this reason, sheathless CE/ESI is a subject of conceptual and technical upgrading more than any other liquid-based separation method hyphenated to MS. Here, recent innovations in sheathless CE/ESI-MS interfacing are gathered in a survey covering the 2005/2006 period. In the first part of the review, the current concepts and methods for in-laboratory production of sturdy designs based on either conductive emitters or electrodeless interfaces are described. The second part is dedicated to microchip CE platforms with externally connected emitters for sheathless coupling to ESI-MS and advanced microfluidic devices integrating CE and sheathless electrospray in a single chip substrate. The advantages, limitations and feasibility for certain applications of all these systems as well as the perspectives for their performance improvement are concurrently assessed.

Polymerase chain reaction in miniaturized systems: big progress in little devices.

A critical need exists for advanced technologies that enable genomic-based DNA analysis to be performed with significantly higher throughput and at a significantly lower cost than is attainable with current hardware. Miniaturized polymerase chain reaction systems offer an attractive platform to address these needs, combining the ability to perform rapid thermocycling with a portable device format that can be inexpensively mass produced. We review recent efforts aimed at developing these next-generation systems and discuss some of the practical considerations involved in adapting this technology for routine laboratory use.

Recent advances in polymeric monolithic stationary phases for electrochromatography in capillaries and chips.

This review article summarizes the advances made over the last two years in polymeric monoliths for capillary electrochromatography (CEC). It covers the scientific literature in the period extending form the second half of 2002 until the end of first half of 2004. Currently, there is an increasing interest in monolithic stationary phases in CEC as an alternative to particulate packed capillary columns due in major part to the simplicity of the in situ preparation of monolithic stationary phases and the availability of a wide chemistry for surface ligands, which allow for tailoring the chromatographic sorbent needed for solving a given separation problem(s). The various approaches, formats, and chemistries used for the preparation of monolithic stationary phases are described.