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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.
The review presents an evaluation of the development of on-line, at-line and in-line sample treatment coupled with capillary and microchip electrophoresis over the last 10 years. In the first part, it describes different types of flow-gating interfaces (FGI) such as cross-FGI, coaxial-FGI, sheet-flow-FGI, and air-assisted-FGI and their fabrication using molding into polydimethylsiloxane and commercially available fittings. The second part deals with the coupling of capillary and microchip electrophoresis with microdialysis, solid-phase, liquid-phase, and membrane based extraction techniques. It mainly focuses on modern techniques such as extraction across supported liquid membrane, electroextraction, single drop microextraction, head space microextraction, and microdialysis with high spatial and temporal resolution. Finally, the design of sequential electrophoretic analysers and fabrication of SPE microcartridges with monolithic and molecularly imprinted polymeric sorbents are discussed. Applications include the monitoring of metabolites, neurotransmitters, peptides and proteins in body fluids and tissues to study processes in living organisms, as well as the monitoring of nutrients, minerals and waste compounds in food, natural and wastewater.
- MeSH
- elektroforéza kapilární metody MeSH
- elektroforéza mikročipová * metody MeSH
- mikrodialýza MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
The emergence of drug-resistant bacteria and new or changing infectious pathogens is an important public health problem as well as a serious socioeconomic concern. Immunomagnetic separation-based methods create new possibilities for rapidly recognizing many of these pathogens. Nanomaterial-based techniques including fluorescent labeling by quantum dots as well as immunoextraction by magnetic particles are excellent tools for such purposes. Moreover, the combination with capillary electrophoresis in miniaturized microchip arrangement brings numerous benefits such as fast and rapid analysis, low sample consumption, very sensitive electrochemical and fluorescent detection, portable miniaturized instrumentation, and rapid and inexpensive device fabrication. Here the use of superparamagnetic particle-based fully automated instrumentation to isolate pathogen Staphylococcus aureus and its Zn(II)-containing proteins (Zn-proteins) is reported using a robotic pipetting system speeding up the sample preparation and enabling to analyze 48 real samples within 6 h. Cell lysis and Zn-protein extractions were obtained from a minimum of 100 cells with the sufficient yield for SDS-PAGE (several tens ng of proteins).
- MeSH
- bakteriální proteiny izolace a purifikace MeSH
- elektroforéza kapilární metody MeSH
- elektroforéza mikročipová metody MeSH
- imunomagnetická separace metody MeSH
- kvantové tečky * MeSH
- Staphylococcus aureus chemie izolace a purifikace MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Amino acids are essential compounds for living organisms, and their determination in biological fluids is crucial for the clinical analysis and diagnosis of many diseases. However, the detection of most amino acids is hindered by the lack of a strong chromophore/fluorophore or electrochemically active group in their chemical structures. The highly sensitive determination of amino acids often requires derivatization. Capillary electrophoresis is a separation technique with excellent characteristics for the analysis of amino acids in biological fluids. Moreover, it offers the possibility of precapillary, on-capillary, or postcapillary derivatization. Each derivatization approach has specific demands in terms of the chemistry involved in the derivatization, which is discussed in this review. The family of homocyclic o-dicarboxaldehyde compounds, namely o-phthalaldehyde, naphthalene-2,3-dicarboxaldehyde, and anthracene-2,3-dicarboxaldehyde, are powerful derivatization reagents for the determination of amino acids and related compounds. In the presence of suitable nucleophiles they react with the primary amino group to form both fluorescent and electroactive derivatives. Moreover, the reaction rate enables all of the derivatization approaches mentioned above. This review focuses on articles that deal with using these reagents for the derivatization of amino acids and related compounds for ultraviolet-visible spectrometry, fluorescence, or electrochemical detection. Applications in capillary and microchip electrophoresis are summarized and discussed.
This review article summarises aspects of the determination of amino acids using capillary and chip electrophoresis in combination with contactless conductivity detection from their historical beginnings to the present time. Discussion is included of the theory of conductivity detection in electromigration techniques, the design of contactless conductivity cells for detection in capillaries and on microchips, including the use of computer programs for simulation of the conductivity response and the process of the electrophoretic separation of amino acids. Emphasis is placed on optimisation of the background electrolyte composition, chiral separation, multidimensional separation, stacking techniques and the use of multidetection systems. There is also a description of clinical applications, the determination of amino acids in foodstuffs, waters, soils and composts with emphasis on modern techniques of sample treatment, such as microdialysis, liquid membrane extraction and many other techniques.
This review presents the developments and applications of microchip electromigration methods in the separation and analysis of peptides and proteins in the period 2011-mid-2016. The developments in sample preparation and preconcentration, microchannel material, and surface treatment are described. Separations by various microchip electromigration methods (zone electrophoresis in free and sieving media, affinity electrophoresis, isotachophoresis, isoelectric focusing, electrokinetic chromatography, and electrochromatography) are demonstrated. Advances in detection methods are reported and novel applications in the areas of proteomics and peptidomics, quality control of peptide and protein pharmaceuticals, analysis of proteins and peptides in biomatrices, and determination of physicochemical parameters are shown.
Point-of-care systems based on microchip capillary electrophoresis require single-use, disposable microchips prefilled with all necessary solutions so an untrained operator only needs to apply the sample and perform the analysis. While microchip fabrication can be (and has been) standardized, some manufacturing differences between microchips are unavoidable. To improve analyte precision without increasing device costs or introducing additional error sources, we recently proposed the use of integrated internal standards (ISTDs): ions added to the BGE in small concentrations which form system peaks in the electropherogram that can be used as a measurement reference. Here, we further expand this initial proof-of-principle test to study a clinically-relevant application of K ion concentrations in human blood; however, using a mock blood solution instead of real samples to avoid interference from other obstacles (e.g. cell lysis). Cs as an integrated ISTD improves repeatability of K ion migration times from 6.97% to 0.89% and the linear calibration correlation coefficient (R2 ) for K quantification from 0.851 to 0.967. Peak area repeatability improves from 11.6-13.3% to 4.75-5.04% at each K concentration above the LOQ. These results further validate the feasibility of using integrated ISTDs to improve imprecision in disposable microchip CE devices by demonstrating their application for physiological samples.
The review brings a comprehensive overview of recent developments and applications of high performance capillary and microchip electroseparation methods (zone electrophoresis, isotachophoresis, isoelectric focusing, affinity electrophoresis, electrokinetic chromatography, and electrochromatography) to analysis, microscale isolation, purification, and physicochemical and biochemical characterization of peptides in the years 2015, 2016, and ca. up to the middle of 2017. Advances in the investigation of electromigration properties of peptides and in the methodology of their analysis (sample preseparation, preconcentration and derivatization, adsorption suppression and EOF control, and detection) are described. New developments in particular CE and CEC methods are presented and several types of their applications to peptide analysis are reported: qualitative and quantitative analysis, determination in complex (bio)matrices, monitoring of chemical and enzymatical reactions and physical changes, amino acid, sequence and chiral analysis, and peptide mapping of proteins. Some micropreparative peptide separations are shown and capabilities of CE and CEC methods to provide important physicochemical characteristics of peptides are demonstrated.
- MeSH
- aminokyseliny chemie MeSH
- chemická frakcionace MeSH
- elektroforéza kapilární metody MeSH
- lidé MeSH
- mikročipová analýza metody MeSH
- peptidové mapování MeSH
- peptidy analýza izolace a purifikace MeSH
- stereoizomerie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
This review brings a survey of the literature on analytical isotachophoresis (ITP) from the years 2010-2012. It confirms the fact that ITP alone is not used for analyses frequently but that its online combinations with other methods are of paramount importance. This review shows that the inherent features of the technique and first of all its concentrating ability are still unique for reaching high sensitivity and efficient sample cleanup in analytical applications. The part devoted to theory is mostly represented by computer simulations and confirms the power and significance of this approach. The section oriented at instrumentation and techniques shows the advantages of ITP in column combinations and microchip techniques. The chapter reviewing the applications is categorized according to the techniques applied, viz., column switching, on line ITP-CZE and on-chip analyses. The final part of the review is devoted to the nearly omnipresent electrophoresis principle of transient isotachophoresis, and to the advantages that it may offer for detection and sampling. In all parts, the significance of the operational conditions is also considered and where possible, the electrolyte system is explicitly presented.
This review summarizes recent developments and applications of capillary and microchip electroseparation methods in proteomic and peptidomic analyses since the year 2015 to ca. mid 2018. Sample preparation procedures for the removal of interfering components or for pre-fractionation and preconcentration of proteins and peptides of interest are discussed. The innovations in coupling of capillary or microchip electroseparation methods with different modes of mass spectrometry detection are covered. In addition, significant recent applications of capillary electromigration methods in both bottom-up and top-down proteomics as well as in determinations of post-translational modifications of proteins are presented. Moreover, several examples of the utilization of capillary electromigration methods coupled with mass spectrometry detection for clinical proteomics and peptidomics are described.
