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Recent advances on multidimensional liquid chromatography–mass spectrometry for proteomics: From qualitative to quantitative analysis—A review
29 May 2012,
10:23:39
Publication year:
2012
Source:Analytica Chimica Acta, Volume 731
Qi Wu, Huiming Yuan, Lihua Zhang, Yukui Zhang
With the acceleration of proteome research, increasing attention has been paid to multidimensional liquid chromatography–mass spectrometry (MDLC–MS) due to its high peak capacity and separation efficiency. Recently, many efforts have been put to improve MDLC-based strategies including “top-down” and “bottom-up” to enable highly sensitive qualitative and quantitative analysis of proteins, as well as accelerate the whole analytical procedure. Integrated platforms with combination of sample pretreatment, multidimensional separations and identification were also developed to achieve high throughput and sensitive detection of proteomes, facilitating highly accurate and reproducible quantification. This review summarized the recent advances of such techniques and their applications in qualitative and quantitative analysis of proteomes.
Source:Analytica Chimica Acta, Volume 731
Qi Wu, Huiming Yuan, Lihua Zhang, Yukui Zhang
With the acceleration of proteome research, increasing attention has been paid to multidimensional liquid chromatography–mass spectrometry (MDLC–MS) due to its high peak capacity and separation efficiency. Recently, many efforts have been put to improve MDLC-based strategies including “top-down” and “bottom-up” to enable highly sensitive qualitative and quantitative analysis of proteins, as well as accelerate the whole analytical procedure. Integrated platforms with combination of sample pretreatment, multidimensional separations and identification were also developed to achieve high throughput and sensitive detection of proteomes, facilitating highly accurate and reproducible quantification. This review summarized the recent advances of such techniques and their applications in qualitative and quantitative analysis of proteomes.
Graphical abstract
Graphical abstract Highlights
► We discuss progress of MDLC–MS systems in qualitative and quantitative proteomics. ► Both “Top-down” and “bottom-up” strategies are discussed in detail. ► On-line integrations of stable isotope labeling process are highlighted. ► This review gives insights into further directions for higher level integration.Multivariate curve resolution combined with gas chromatography to enhance analytical separation in complex samples: A review
29 May 2012,
10:23:39
Publication year:
2012
Source:Analytica Chimica Acta, Volume 731
Leandro Wang Hantao, Helga Gabriela Aleme, Marcio Pozzobon Pedroso, Guilherme Post Sabin, Ronei Jesus Poppi, Fabio Augusto
This review describes the major advantages and pitfalls of iterative and non-iterative multivariate curve resolution (MCR) methods combined with gas chromatography (GC) data using literature published since 2000 and highlighting the most important combinations of GC coupled to mass spectrometry (GC–MS) and comprehensive two-dimensional gas chromatography with flame ionization detection (GC×GC-FID) and coupled to mass spectrometry (GC×GC–MS). In addition, a brief summary of some pre-processing strategies will be discussed to correct common issues in GC, such as retention time shifts and baseline/background contributions. Additionally, algorithms such as evolving factor analysis (EFA), heuristic evolving latent projection (HELP), subwindow factor analysis (SFA), multivariate curve resolution-alternating least squares (MCR-ALS), positive matrix factorization (PMF), iterative target transformation factor analysis (ITTFA) and orthogonal projection resolution (OPR) will be described in this paper. Even more, examples of applications to food chemistry, lipidomics and medicinal chemistry, as well as in essential oil research, will be shown. Lastly, a brief illustration of the MCR method hierarchy will also be presented.
Source:Analytica Chimica Acta, Volume 731
Leandro Wang Hantao, Helga Gabriela Aleme, Marcio Pozzobon Pedroso, Guilherme Post Sabin, Ronei Jesus Poppi, Fabio Augusto
This review describes the major advantages and pitfalls of iterative and non-iterative multivariate curve resolution (MCR) methods combined with gas chromatography (GC) data using literature published since 2000 and highlighting the most important combinations of GC coupled to mass spectrometry (GC–MS) and comprehensive two-dimensional gas chromatography with flame ionization detection (GC×GC-FID) and coupled to mass spectrometry (GC×GC–MS). In addition, a brief summary of some pre-processing strategies will be discussed to correct common issues in GC, such as retention time shifts and baseline/background contributions. Additionally, algorithms such as evolving factor analysis (EFA), heuristic evolving latent projection (HELP), subwindow factor analysis (SFA), multivariate curve resolution-alternating least squares (MCR-ALS), positive matrix factorization (PMF), iterative target transformation factor analysis (ITTFA) and orthogonal projection resolution (OPR) will be described in this paper. Even more, examples of applications to food chemistry, lipidomics and medicinal chemistry, as well as in essential oil research, will be shown. Lastly, a brief illustration of the MCR method hierarchy will also be presented.
Graphical abstract
Graphical abstract Highlights
► An insight on advantages and pitfalls of CR and GC data since 2000. ► GC–MS and GC×GC applications will be addressed. ► The state-of-art of new algorithms will be presented.Chemometric evaluation of different experimental conditions on wheat (Triticum aestivum L.) development using liquid chromatography mass spectrometry (LC–MS) profiles of benzoxazinone derivatives
29 May 2012,
10:23:39
Publication year:
2012
Source:Analytica Chimica Acta, Volume 731
Mireia Farrés, Marta Villagrasa, Ethel Eljarrat, Damià Barceló, Romà Tauler
Different chemometric techniques have been used to evaluate the effect of distinct experimental conditions and factors on Triticum aestivum L. plant development. The study was conducted using three wheat varieties, Astron, Ritmo and Stakado. These varieties were grown under organic and conventional cultivation systems. Samples were collected at five growth stages. Shoots and roots of each plant at these stages were analysed. Three replicates of each analysed sample were performed to improve representativeness and to allow for the evaluation of natural variability and interaction effects. All samples were analysed using Liquid Chromatography Mass–Spectrometry (LC–MS), and the Total Ion Current (TIC) profiles of benzoxazinone derivatives obtained for each sample were investigated. Qualitative and quantitative assessments of these TIC profiles and of their changes in the analysed samples were carried out using different chemometric techniques. Estimation of main effects, and of their possible interaction, was performed by means of Analysis of Variance combined to Principal Component Analysis (ANOVA–PCA) and of Analysis of Variance combined to Simultaneous Component Analysis (ASCA).
Source:Analytica Chimica Acta, Volume 731
Mireia Farrés, Marta Villagrasa, Ethel Eljarrat, Damià Barceló, Romà Tauler
Different chemometric techniques have been used to evaluate the effect of distinct experimental conditions and factors on Triticum aestivum L. plant development. The study was conducted using three wheat varieties, Astron, Ritmo and Stakado. These varieties were grown under organic and conventional cultivation systems. Samples were collected at five growth stages. Shoots and roots of each plant at these stages were analysed. Three replicates of each analysed sample were performed to improve representativeness and to allow for the evaluation of natural variability and interaction effects. All samples were analysed using Liquid Chromatography Mass–Spectrometry (LC–MS), and the Total Ion Current (TIC) profiles of benzoxazinone derivatives obtained for each sample were investigated. Qualitative and quantitative assessments of these TIC profiles and of their changes in the analysed samples were carried out using different chemometric techniques. Estimation of main effects, and of their possible interaction, was performed by means of Analysis of Variance combined to Principal Component Analysis (ANOVA–PCA) and of Analysis of Variance combined to Simultaneous Component Analysis (ASCA).
Graphical abstract
Graphical abstract Highlights
► LC–MS metabolite profiles are investigated with ANOVA–PCA and ASCA. ► Growth stage and tissue sample factors were found to affect wheat culture. ► DIMBOA-Glc, DMBOA, HMBOA and MBOA proved to be significant metabolites.Optimization of antibiotic analysis in water by solid-phase extraction and high performance liquid chromatography–mass spectrometry/mass spectrometry
29 May 2012,
10:23:39
Publication year:
2012
Source:Analytica Chimica Acta, Volume 731
John L. Zhou, Khalid Maskaoui, Adeleye Lufadeju
This paper describes the development of an optimized method based on solid-phase extraction (SPE) followed by liquid chromatography–electrospray ionization tandem mass spectrometry (LC–MS/MS) for the simultaneous analysis of ten antibiotic compounds including tetracyclines, sulfonamides, macrolides and quinolones. LC–MS/MS sensitivity has been optimized by alterations to both LC and MS operations. Of the two high resolution columns tested, Waters Symmetry C18 endcapped and Agilent Zorbax Bonus-RP, the latter was found to show better performance in producing sharp peaks and clear separation for most of the target compounds. Optimization of the MS fragmentation collision and cone energy enhanced the peak areas of the target analytes. The recovery of the target compounds from water samples was most efficient on Waters Oasis HLB SPE cartridge, while methanol was shown to be the most suitable solvent for desorbing the compounds from SPE. In addition, acidification of samples prior to SPE was shown to enhance the recovery of the compounds. To ensure a satisfactory recovery, the flow rate through SPE should be maintained at ≤10mLmin−1. The method was successfully applied to the analysis of antibiotics from environmental water samples, with concentrations being <LOD in tap water, between <LOD to 28ngL−1 in river water and between <LOD to 230ngL−1 in sewage effluent.
Source:Analytica Chimica Acta, Volume 731
John L. Zhou, Khalid Maskaoui, Adeleye Lufadeju
This paper describes the development of an optimized method based on solid-phase extraction (SPE) followed by liquid chromatography–electrospray ionization tandem mass spectrometry (LC–MS/MS) for the simultaneous analysis of ten antibiotic compounds including tetracyclines, sulfonamides, macrolides and quinolones. LC–MS/MS sensitivity has been optimized by alterations to both LC and MS operations. Of the two high resolution columns tested, Waters Symmetry C18 endcapped and Agilent Zorbax Bonus-RP, the latter was found to show better performance in producing sharp peaks and clear separation for most of the target compounds. Optimization of the MS fragmentation collision and cone energy enhanced the peak areas of the target analytes. The recovery of the target compounds from water samples was most efficient on Waters Oasis HLB SPE cartridge, while methanol was shown to be the most suitable solvent for desorbing the compounds from SPE. In addition, acidification of samples prior to SPE was shown to enhance the recovery of the compounds. To ensure a satisfactory recovery, the flow rate through SPE should be maintained at ≤10mLmin−1. The method was successfully applied to the analysis of antibiotics from environmental water samples, with concentrations being <LOD in tap water, between <LOD to 28ngL−1 in river water and between <LOD to 230ngL−1 in sewage effluent.
Graphical abstract
Graphical abstract Highlights
► A multi-residue analytical method has been developed for antibiotics. ► Oasis HLB SPE is the best cartridge for sample extraction. ► SPE flow rate should not exceed 10mLmin−1. ► Sample acidification enhances recovery. ► Zorbax column performs better than C18 column in antibiotic separation.Molecularly imprinted polymer coated solid-phase microextraction fiber prepared by surface reversible addition–fragmentation chain transfer polymerization for monitoring of Sudan dyes in chilli tomato sauce and chilli pepper samples
29 May 2012,
10:23:39
Publication year:
2012
Source:Analytica Chimica Acta, Volume 731
Xiaogang Hu, Yanan Fan, Yi Zhang, Guimei Dai, Quanling Cai, Yujuan Cao, Changjuan Guo
Surface reversible addition-fragmentation chain transfer (RAFT) polymerization method was firstly applied to the preparation of molecularly imprinted polymer (MIP) coated silicon solid-phase microextraction (SPME) fibers. With Sudan I as template, an ultra-thin MIP coating with about 0.55-μm thickness was obtained with homogeneous structure and controlled composition, due to the controllable radical growing and chain propagation in surface RAFT polymerization. The MIP-coated fibers were found with enhanced selectivity coefficients (3.0–6.5) to Sudan I–IV dyes in contrast with those reported in our previous work. Furthermore, the ultra-thin thickness of MIP coating was helpful to the effective elution of template and fast adsorption/desorption kinetics, so only about 18min was needed for MIP-coated SPME operation. The detection limits of 21–55ngL−1 were achieved for four Sudan dyes, when MIP-coated SPME was coupled with liquid chromatography (LC) and mass spectrometry (MS) detection. The MIP-coated SPME–LC–MS/MS method was tested for the monitoring of ultra trace Sudan dyes in spiked chilli tomato sauce and chilli pepper samples, and high enrichment effect, remarkable matrix peaks-removing capability, and consequent high sensitivities were achieved to four Sudan dyes.
Source:Analytica Chimica Acta, Volume 731
Xiaogang Hu, Yanan Fan, Yi Zhang, Guimei Dai, Quanling Cai, Yujuan Cao, Changjuan Guo
Surface reversible addition-fragmentation chain transfer (RAFT) polymerization method was firstly applied to the preparation of molecularly imprinted polymer (MIP) coated silicon solid-phase microextraction (SPME) fibers. With Sudan I as template, an ultra-thin MIP coating with about 0.55-μm thickness was obtained with homogeneous structure and controlled composition, due to the controllable radical growing and chain propagation in surface RAFT polymerization. The MIP-coated fibers were found with enhanced selectivity coefficients (3.0–6.5) to Sudan I–IV dyes in contrast with those reported in our previous work. Furthermore, the ultra-thin thickness of MIP coating was helpful to the effective elution of template and fast adsorption/desorption kinetics, so only about 18min was needed for MIP-coated SPME operation. The detection limits of 21–55ngL−1 were achieved for four Sudan dyes, when MIP-coated SPME was coupled with liquid chromatography (LC) and mass spectrometry (MS) detection. The MIP-coated SPME–LC–MS/MS method was tested for the monitoring of ultra trace Sudan dyes in spiked chilli tomato sauce and chilli pepper samples, and high enrichment effect, remarkable matrix peaks-removing capability, and consequent high sensitivities were achieved to four Sudan dyes.
Graphical abstract
Graphical abstract Highlights
► Surface RAFT polymerization was firstly applied to MIP-coated fiber preparation. ► Ultra-thin MIP coating of about 0.55μm was obtained with homogenous structure. ► MIP-coated fiber showed improved selectivities to Sudan I–IV dyes. ► MIP-coated SPME–LC–MS/MS method was used for monitoring of trace Sudan dyes.Quantitative selenium speciation in human urine by using liquid chromatography–electrospray tandem mass spectrometry
29 May 2012,
10:23:39
Publication year:
2012
Source:Analytica Chimica Acta, Volume 731
Ying Lu, Alice Rumpler, Kevin A. Francesconi, Spiros A. Pergantis
A liquid chromatography–electrospray-tandem mass spectrometry (ES-MS/MS) method was developed for the speciation analysis of four organic selenium species of relevance to human urinary metabolism, namely trimethylselenomium ion (TMSe+), selenomethionine (SeMet) and the two selenosugars, methyl 2-acetamido-2-deoxy-1-seleno-β-d-galactos/-glucos-amine (SeGalNAc and SeGluNAc, respectively). Their chromatographic separation was achieved by using a cation exchange pre-column coupled in-series with a reversed-phase high-performance liquid chromatography column, along with an isocratic mobile phase. Online detection was performed using ES-MS/MS in selective reaction monitoring mode. SeGalNAc was detected as the major human urinary metabolite of selenium in the samples analysed, whereas TMSe+ was detected in the urine of one volunteer before and after receiving a selenium supplement. SeMet was not detected as a urine excretory metabolite in this study. Spiking experiments performed with the urine samples revealed significant signal suppression caused by coeluting matrix constituents. To overcome such interferences, isotopically labelled 13CD3 82SeGalNAc was used as an internal standard, whereas in the absence of an isotopically labelled internal standard for TMSe+, the standard addition method was applied. Quality control for the accurate quantitation of TMSe+ and SeGalNAc was carried out by analysing spiked human urine samples with appropriate selenium standards over a concentration range of 10–50μgSeL−1. The method has achieved a limit of detection in the presence of urine matrix comparable to that of HPLC-inductively coupled plasma-mass spectrometry for the four selenium species: 1.0μgSeL−1 for TMSe+, 5.6μgSeL−1 for SeMet, and 0.1μgSeL−1 for both SeGalNAc and SeGluNAc.
Source:Analytica Chimica Acta, Volume 731
Ying Lu, Alice Rumpler, Kevin A. Francesconi, Spiros A. Pergantis
A liquid chromatography–electrospray-tandem mass spectrometry (ES-MS/MS) method was developed for the speciation analysis of four organic selenium species of relevance to human urinary metabolism, namely trimethylselenomium ion (TMSe+), selenomethionine (SeMet) and the two selenosugars, methyl 2-acetamido-2-deoxy-1-seleno-β-d-galactos/-glucos-amine (SeGalNAc and SeGluNAc, respectively). Their chromatographic separation was achieved by using a cation exchange pre-column coupled in-series with a reversed-phase high-performance liquid chromatography column, along with an isocratic mobile phase. Online detection was performed using ES-MS/MS in selective reaction monitoring mode. SeGalNAc was detected as the major human urinary metabolite of selenium in the samples analysed, whereas TMSe+ was detected in the urine of one volunteer before and after receiving a selenium supplement. SeMet was not detected as a urine excretory metabolite in this study. Spiking experiments performed with the urine samples revealed significant signal suppression caused by coeluting matrix constituents. To overcome such interferences, isotopically labelled 13CD3 82SeGalNAc was used as an internal standard, whereas in the absence of an isotopically labelled internal standard for TMSe+, the standard addition method was applied. Quality control for the accurate quantitation of TMSe+ and SeGalNAc was carried out by analysing spiked human urine samples with appropriate selenium standards over a concentration range of 10–50μgSeL−1. The method has achieved a limit of detection in the presence of urine matrix comparable to that of HPLC-inductively coupled plasma-mass spectrometry for the four selenium species: 1.0μgSeL−1 for TMSe+, 5.6μgSeL−1 for SeMet, and 0.1μgSeL−1 for both SeGalNAc and SeGluNAc.
Graphical abstract
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