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1.
Calvano CD Aresta A Palmisano F Zambonin CG 《Analytical and bioanalytical chemistry》2007,389(7-8):2075-2084
Laser desorption ionization time-of-flight mass spectrometry (LDI–TOF MS) was used to characterize olive and sunflower oils
before and after thermally assisted oxidation in order to develop a rapid fingerprinting method for oil that contains unchanged
and oxidized components. No matrix was used to assist laser desorption, and simplified mass spectra were obtained in the mass
range of interest (m/z 500–1000), where triacyl- and diacylglycerol ions were observed. Sample preparation was reduced to dissolving oil in chloroform
saturated with NaCl. Sodiated triacylglycerols (TAGs), their epoxy/hydroxy and hydroperoxy derivatives, as well as TAGs with
shortened chain fatty acids (β-scission products) were clearly observed in the spectra. LDI–TOF MS rapidly provides semiquantitative information about the
oxidation level of edible oil, and thus represents a very useful quality control tool.
Dedicated to Professor Pier Giorgio Zambonin on the occasion of his 72nd birthday. 相似文献
2.
The rapid development of nanotechnology has revolutionized scientific developments in recent decades. Mass spectrometry (MS)
measurements are no exception and have benefited greatly from integration of nanomaterials in every step of analysis. This
brief review summarizes recent developments in the field with the focus on the use of nanomaterials as alternative media to
facilitate analyte ionization in laser-desorption ionization–mass spectrometry (LDI–MS) and secondary ion mass spectrometry
(SIMS). The biological applications of both techniques are also detailed. The use of nanomaterials in other aspects of MS
analysis, for example in sample clean-up and indirect analyte quantification, is briefly discussed. 相似文献
3.
Van Elslande E Guérineau V Thirioux V Richard G Richardin P Laprévote O Hussler G Walter P 《Analytical and bioanalytical chemistry》2008,390(7):1873-1879
Microsamples of pink cosmetic powders from the Greco–Roman period were analyzed using two complementary analytical approaches
for identification of the colouring agents (lake pigments originally manufactured from madder plants with an inert binder,
usually a metallic salt) present in the samples. The first technique was a methanolic acidic extraction of the archaeological
samples with an additional ethyl acetate extraction of the anthraquinone-type colouring agents which were identified using
high performance liquid chromatography coupled to electrospray ionization with high resolution mass spectrometry (LC–ESI–HRMS),
and the second was direct analysis of a microsample by laser desorption ionization–mass spectrometry (LDI–MS). The latter
technique is well suited when the quantity of samples is very low. This soft ionization technique enables the detection of
very small quantities of compounds using the combination of positive and negative-ion modes. It was also successfully applied
for the direct analysis of some laboratory-made reference compounds. However, the presence of lead in one of these ancient
samples induced a spectral suppression phenomenon. In this case and conditional on a sufficient quantity of available sample,
the former method is better adapted for the characterization of these anthraquinone-type molecules. This study also confirmed
that purpurin, munjistin, and pseudopurpurin are the principal colouring agents present in these ancient cosmetic powders
constituted from madder plants.
Presented at the Annual French National Symposium on Mass Spectrometry, Electrophoresis and Proteomics, 20–23 September 2007
in Pau, France. 相似文献
4.
Zhang J Dong X Cheng J Li J Wang Y 《Journal of the American Society for Mass Spectrometry》2011,22(7):1294-1298
In this Application Note, we describe, for the first time, the rapid analysis of hydrophobic compounds present in environmental
contaminants, which includes polycyclic aromatic hydrocarbons (PAHs) and estrogen, by matrix-assisted laser desorption/ionization
time-of-flight mass spectrometry (MALDI-TOF MS) with the use of graphene as matrix. MALDI-TOF MS with conventional matrix
has limitations in analyzing low-polarity compounds owing to their difficulty in ionization. We demonstrate that compared
with conventional matrix, graphene displays higher desorption/ionization efficiencies for PAHs, and no fragment ions are observed.
The method also holds potential in quantitative analysis. In addition, the ionization signal increases with the increasing
number of benzene rings in the PAHs, suggesting that graphene binds to PAHs via π–π stacking interactions. Furthermore, graphene
as adsorbent for solid-phase extraction of coronene from river water sample displays good performance with a detection limit
of 10–7 M. This work provides a novel and convenient method for analyzing low-polarity environmental contaminants by MALDI-TOF MS. 相似文献
5.
Oberacher H 《Analytical and bioanalytical chemistry》2008,391(1):135-149
After completion of the human genome sequence the search for differences among individual genomes has become the centre of
focus for geneticists. Two different types of polymorphism—single nucleotide polymorphisms (SNPs) and short tandem repeats
(STRs)—are major sources of genetic diversity and are of widespread use in genetic analysis. A plethora of genotyping techniques
have been developed, and mass spectrometry (MS) is among the most widely used analytical platforms. The most striking advantage
of mass spectrometric genotyping assays over others is the use of the measured molecular mass information for allele calling.
The molecular mass is less error-prone than other sequence-specific parameters, including migration times, retention times,
or hybridization yields, as it represents an intrinsic property of a nucleic acid molecule that is directly related to its
nucleotide composition. Mass spectrometric assays can roughly be divided into two major groups—matrix-assisted laser desorption/ionization
(MALDI)-based and electrospray ionization (ESI)-based assays. An important subdivision of ESI-based genotyping methods are
approaches that originate from the hyphenation of liquid chromatography (LC) to MS. The principles of these three classes
of mass spectrometric genotyping techniques are summarized in this review. Possibilities and limitations are critically discussed
to assist scientists, especially non-experts in MS, in choosing the appropriate mass spectrometric assay for genotyping a
genetic marker of interest.
Figure Comparison of the principle workflows applied for the characterization of genetic markers by MALDI–MS, ESI–MS, and LC–MS 相似文献
6.
Glutathione peroxidase (isolated from bovine erythrocytes) and its behaviour during alkylation and enzymatic digestion were
studied by various hyphenated techniques: gel electrophoresis–laser ablation (LA) inductively coupled plasma (ICP) mass spectrometry
(MS), size-exclusion liquid chromatography–ICP MS, capillary high-performance liquid chromatography (capHPLC)–ICP MS, matrix-assisted
laser desorption/ionization (MALDI) time-of-flight (TOF) MS, electrospray MS, and nanoHPLC–electrospray ionization (ESI) MS/MS.
ESI TOF MS and MALDI TOF MS allowed the determination of the molecular mass but could not confirm the presence of selenium
in the protein. The purity of the protein with respect to selenium species could be evaluated by LA ICP MS and size-exclusion
chromatography (SEC)–ICP MS under denaturating and nondenaturating conditions, respectively. SEC–ICP MS and capHPLC–ICP MS
turned out to be valuable techniques to study the enzymolysis efficiency, miscleavage and artefact formation during derivatization
and tryptic digestion. For the first time the parallel ICP MS and ESI MS/MS data are reported for the selenocysteine-containing
peptide extracted from the gel; capHPLC–ICP MS allowed the sensitive detection of the selenopeptide regardless of the matrix
and nanoHPLC–electrospray made possible its identification.
Figure Eye catching image
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
Elisabeth Schramm Jasper H?lzer Michael Pütz Rasmus Schulte-Ladbeck Rainer Schultze Martin Sklorz Andreas Ulrich Jochen Wieser Ralf Zimmermann 《Analytical and bioanalytical chemistry》2009,395(6):1795-1807
For the detection of security-relevant substances at low concentrations in complex matrices, coupling of thermal desorption–single
photon ionization–ion trap mass spectrometry (TD-SPI-ITMS) was successfully tested. The main advantage of taking solid samples
with a wipe pad followed by thermal desorption is the low detection limit by enhanced vapor pressure. Single photon ionization
is a soft ionization technique which reduces the target ion fragmentation and shields bulk components with high ionization
energies (IE) like nitrogen yielding to clearly arranged mass spectra with significant high mass peaks. To obtain low false-positive
and false-negative rates, especially necessary for security-relevant substances, the ion trap mass spectrometer allows identification
of signals with MS/MS studies. In this concept, the soft ionization technique fits well with the MS/MS studies, as peaks with
high masses are generated yielding significant MS/MS fragments. For the ionization, photon energies between about 8 eV (155 nm)
and 12 eV (103 nm) were generated with electron-beam-pumped rare gas excimer lamps (EBEL). Depending on the rare gas used,
light with different photon energy is generated, adapted to the substances of interest. So, even most narcotics, having relatively
low IEs, can be ionized with 8.4 eV photons without massive fragmentation. For most explosives, photons with higher energy
must be used as their IEs are higher. In this work, a mobile setup with a commercial ion trap mass spectrometer has been developed
and tested. Even a first real-scenario measurement campaign was accomplished successfully proving the field-suitability of
the system. 相似文献
8.
Ambient mass spectrometry: bringing MS into the “real world” 总被引:1,自引:0,他引:1
Rosana M. Alberici Rosineide C. Simas Gustavo B. Sanvido Wanderson Romão Priscila M. Lalli Mario Benassi Ildenize B. S. Cunha Marcos N. Eberlin 《Analytical and bioanalytical chemistry》2010,398(1):265-294
Mass spectrometry has recently undergone a second contemporary revolution with the introduction of a new group of desorption/ionization
(DI) techniques known collectively as ambient mass spectrometry. Performed in an open atmosphere directly on samples in their
natural environments or matrices, or by using auxiliary surfaces, ambient mass spectrometry (MS) has greatly simplified and
increased the speed of MS analysis. Since its debut in 2004 there has been explosive growth in the applications and variants
of ambient MS, and a very comprehensive set of techniques based on different desorption and ionization mechanisms is now available.
Most types of molecules with a large range of masses and polarities can be ionized with great ease and simplicity with the
outstanding combination of the speed, selectivity, and sensitivity of MS detection. This review describes and compares the
basis of ionization and the concepts of the most promising ambient MS techniques known to date and illustrates, via typical
analytical and bioanalytical applications, how ambient MS is helping to bring MS analysis deeper than ever into the “real
world” open atmosphere environment—to wherever MS is needed. 相似文献
9.
Nattikarn Kaewkhomdee Sandra Mounicou Joanna Szpunar Ryszard Lobinski Juwadee Shiowatana 《Analytical and bioanalytical chemistry》2010,396(3):1355-1364
Sequential extraction (water, Driselase, protease XIV) and extraction with simulated gastric and intestinal fluids were proposed
to characterize the binding and the bioaccessibility of chromium in two commercial food supplements obtained by incorporation
of this element into yeast. Chromium in Cr-enriched yeast was found to be hardly extractable with water, Driselase, or simulated
gastric fluid (recoveries of approximately 10–20%), but proteolysis or gastrointestinal fluid digestion released more than
half of the chromium present. Fractionation with size-exclusion chromatography with Cr-specific detection by inductively coupled
plasma mass spectrometry (ICP MS) allowed the distinction of two fractions: one below approximately 1 kDa and one 1–5 kDa;
they contained the entirety of the released Cr with proportions varying as a function of the extracting solution and the origin
of sample. When collected and investigated by reversed-phase high-performance liquid chromatography–ICP MS, the low molecular
mass fraction was found to release Cr(III), whereas the heavier one showed most of Cr bound in fairly stable hydrophobic complexes.
However, an attempt of their identification by electrospray ionization MS/MS and matrix-assisted laser desorption ionization
MS was not successful.
相似文献
10.
Aubriet F 《Analytical and bioanalytical chemistry》2007,389(5):1381-1396
The combination of a laser with a Fourier transform ion cyclotron resonance mass spectrometer (FTICRMS) enables a variety
of MS experiments to be conducted. The laser can be used either as an intense photonic source for the photoionization of neutral
species introduced in a variety of ways into the FTICR cell, or it can be made to directly interact with a solid, generating
gas-phase ions. Depending on the experimental conditions used, various laser-matter interactions can occur. When high laser
energy (also referred to as power density or irradiance) is used, laser ablation (LA) processes lead to the release of species
into the gas phase, a significant fraction of which are ionic. The number of ions decreases with the irradiance. For low irradiance
values, the so-called laser desorption (LD) regime applies, where the expelled species are mainly neutrals. LA–FTICRMS and
LD–FTICRMS can be used to study a wide range of materials, including mineral, organic, hybrid and biological compounds (although
matrix-assisted laser desorption ionization, MALDI, which is not reviewed in this paper, is more commonly applied to biological
compounds). This paper will review a selection of methodological developments and applications in the field of laser ionization
FTICRMS, LD–FTICRMS, and LA–FTICRMS for the analysis of organics and inorganics in complex mixtures, emphasizing insoluble
materials. Specifically, silicate- and carbon-based complex materials as well as organic compounds will be examined due to
their relevance to natural environmental and anthropogenic matrices. 相似文献
11.
I. V. Shmygol’ S. V. Snegir V. A. Pokrovskii 《Theoretical and Experimental Chemistry》2007,43(4):272-277
A comparative analysis of the laser desorption/ionization of vitamin B12 by matrix-assisted laser desorption/ionization (MALDI) and desorption/ionization on porous silicon (DIOS) was carried out.
The mass spectra obtained were interpreted and the pathways for ion formation and decomposition were established. The MALDI
fragmentation of the positive vitamin B12 ions is more extensive than the DIOS fragmentation. The most extensive fragmentation was found using the MALDI method for
negative vitamin B12 ions, which are lacking when using the DIOS method.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 4, pp. 251–256, July–August, 2007. 相似文献
12.
Dingyin Tao Lihua Zhang Yichu Shan Zhen Liang Yukui Zhang 《Analytical and bioanalytical chemistry》2011,399(1):229-241
High-performance liquid chromatography–electrospray ionization tandem mass spectrometry (HPLC–ESI-MS–MS) is regarded as one
of the most powerful techniques for separation and identification of proteins. Recently, much effort has been made to improve
the separation capacity, detection sensitivity, and analysis throughput of micro- and nano-HPLC, by increasing column length,
reducing column internal diameter, and using integrated techniques. Development of HPLC columns has also been rapid, as a
result of the use of submicrometer packing materials and monolithic columns. All these innovations result in clearly improved
performance of micro- and nano-HPLC for proteome research. 相似文献
13.
M. Careri L. Elviri A. Lorenzi A. Mangia A. Penna G. Predieri 《Journal of Sol-Gel Science and Technology》2011,60(3):359-365
In this work, sol–gel derived silica films were prepared for direct desorption/ionization of organic compounds in MALDI-TOF–MS
analysis with the aim of improving method precision and of reducing interfering signals at low m/z values. Two commonly used
MALDI matrices, 2,5-dihydroxybenzoic acid (DHB) and α-cyano-4-hydroxycinnamic acid (CHCA), were incorporated into the sol–gel
network in order to absorb laser energy and to induce analyte desorption/ionization with low or absent background signals
in the mass spectra. To achieve a reproducible xerogel film formation, experimental parameters for its deposition were optimized.
The gel matrices were characterized by Fourier Transform Infrared (FT-IR) spectroscopy, X-ray Diffraction (XRD), and Scanning
Electron Microscopy (SEM) analysis. The results proved the embedding of the matrix molecules in a disperse form into the homogeneous
sol–gel material. The sol–gel matrix was then tested for the qualitative and quantitative analysis of two reference peptides,
such as Bradykinin and P14R. In addition, spectral quality and method performance were assessed for quantitation of melamine, a low-molecular weight
compound of food safety concern. In all cases, high quality spectra and excellent mass accuracy (between 3.5 and 13 ppm) were
observed. Furthermore, the experimental results evidenced a significant improvement of the measurement repeatability on spot
and between spots (relative standard deviation <10%), with respect to the traditional dried-droplet sample deposition method.
Good sensitivity and linearity in the concentration range explored were obtained for peptides and melamine, demonstrating
the suitability of the sol–gel-based matrix to be used for quantitative analysis. 相似文献
14.
Gregory D. Schilling Jacob T. Shelley James H. Barnes Roger P. Sperline M. Bonner Denton Charles J. Barinaga David W. Koppenaal Gary M. Hieftje 《Journal of the American Society for Mass Spectrometry》2010,21(1):97-103
An ambient desorption/ionization (ADI) source, known as the flowing atmospheric pressure afterglow (FAPA), has been coupled
to a Mattauch-Herzog mass spectrograph (MHMS) equipped with a focal plane camera (FPC) array detector. The FAPA ionization
source enables direct mass spectral analysis of solids, liquids, and gases through either positive or negative ionization
modes. In either case, spectra are generally simple with dominant peaks being the molecular ions or protonated molecular ions.
Use of the FAPA source with the MHMS allows the FPC detector to be characterized for the determination of molecular species,
whereas previously only atomic mass spectrometry (MS) has been demonstrated. Furthermore, the FPC is shown to be sensitive
to negative ions without the need to change any detector parameters. The analysis of solid, liquid, and gaseous samples through
positive and negative ionization is demonstrated with detection limits (1–25 fmol/s, ∼0. 3–10 pg of analyte per mL of helium)
surpassing those obtained with the FAPA source coupled to a time-of-flight mass analyzer. 相似文献
15.
Polysorbates can be separated according to their functionality and architecture by liquid chromatography on a hydrophilic
interaction chromatography (HILIC) column in acetone–water mobile phases containing 90–97% acetone. The different polymer
homologous series are separated according to the number of terminal hydroxy groups and elute as narrow peaks. The hydrophilic
part (ethoxylates of sorbitan, isosorbide, and poly(ethyleneglycol)) and amphiphilic funtionalites (ethoxylated mono-, di-,
tri-, and tetraesters) were separated by HILIC mode of high-performance liquid chromatography (HPLC). All these separated
functionaities are identified and confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy
(MALDI-TOF MS). This combination of HPLC and MALDI-TOF MS has been proven to be an excellent tool for the characterization
of heterogenous complex samples. 相似文献
16.
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was optimized to discriminate
between wild-type and ampicillin-resistant Escherichia coli. Only ampicillin-resistant E. coli displayed an m/z ≈ 29,000 peak, which was confirmed as β-lactamase by in-gel digestion followed by peptide mass fingerprinting. Rapid MALDI-TOF
MS detection of antibiotic-resistance could fulfill an important clinical need, providing critical phenotypic information
beyond genus–species identification. 相似文献
17.
Artem Akhmetov Jerry F. Moore Gerald L. Gasper Peter J. Koin Luke Hanley 《Journal of mass spectrometry : JMS》2010,45(2):137-145
Vacuum ultraviolet single photon ionization (VUV SPI) is a soft ionization technique that has the potential to address many of the limitations of matrix‐assisted laser desorption/ionization (MALDI) for imaging MS. Laser desorption postionization (LDPI) uses VUV SPI for postionization and is experimentally analogous to a MALDI instrument with the addition of a pulsed VUV light source. This review discusses progress in LDPI‐MS over the last decade, with an emphasis on imaging MS of bacterial biofilms, analytes whose high salt environment make them particularly resistant to imaging by MALDI‐MS. This review first considers fundamental aspects of VUV SPI including ionization mechanisms, cross sections, quantum yields of ionization, dissociation and potential mass limits. The most common sources of pulsed VUV radiation are then described along with a newly constructed LDPI‐MS instrument with imaging capabilities. Next, the detection and imaging of small molecules within intact biofilms is demonstrated by LDPI‐MS using 7.87 eV (157.6 nm) VUV photons from a molecular fluorine excimer laser, followed by the use of aromatic tags for detection of selected species within the biofilm. The final section considers the future prospects for imaging intact biological samples by LDPI‐MS. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
18.
Niina M. Suni Henni Aalto Tiina J. Kauppila Tapio Kotiaho Risto Kostiainen 《Journal of mass spectrometry : JMS》2012,47(5):611-619
In this article, the effect of spray solvent on the analysis of selected lipids including fatty acids, fat‐soluble vitamins, triacylglycerols, steroids, phospholipids, and sphingolipids has been studied by two different ambient mass spectrometry (MS) methods, desorption electrospray ionization‐MS (DESI‐MS) and desorption atmospheric pressure photoionization‐MS (DAPPI‐MS). The ionization of the lipids with DESI and DAPPI was strongly dependent on the spray solvent. In most cases, the lipids were detected as protonated or deprotonated molecules; however, other ions were also formed, such as adduct ions (in DESI), [M‐H]+ ions (in DESI and DAPPI), radical ions (in DAPPI), and abundant oxidation products (in DESI and DAPPI). DAPPI provided efficient desorption and ionization for neutral and less polar as well as for ionic lipids but caused extensive fragmentation for larger and more labile compounds because of a thermal desorption process. DESI was more suitable for the analysis of the large and labile lipids, but the ionization efficiency for less polar lipids was poor. Both methods were successfully applied to the direct analysis of lipids from pharmaceutical and food products. Although DESI and DAPPI provide efficient analysis of lipids, the multiple and largely unpredictable ionization reactions may set challenges for routine lipid analysis with these methods. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
19.
Sonderegger H Rameshan C Lorenz H Klauser F Klerks M Rainer M Bakry R Huck CW Bonn GK 《Analytical and bioanalytical chemistry》2011,401(6):1963-1974
Matrix-assisted laser desorption/ionization-mass spectrometry (MALDI–MS) measurements in the low-molecular-mass region, ranging
from 0 to 1000 Daltons are very often difficult to perform because of signal interferences originating from matrix ions. In
order to overcome this problem, a stainless steel target was coated with a homogeneous titanium dioxide layer. The layer obtained
was further investigated for its ability to desorb small molecules, e.g., amino acids, sugars, poly(ethylene glycol) (PEG)
200, or extracts from Cynara scolymus leaves. The stability of the layer was determined by repeated measurements on the same target location, which was monitored
by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) before and after surface-assisted laser desorption/ionization
(SALDI) analysis. In addition, this titanium dioxide layer was compared with an already published method with titanium dioxide
nanopowder as inorganic matrix. As a result of this work, the titanium dioxide layer produced minimal background interference,
enabling simple interpretation of the detected mass spectra. Furthermore, the TiO2 coating provides a target that can be reused many times for SALDI–MS measurements. 相似文献
20.
Boone M. Prentice 《Journal of mass spectrometry : JMS》2024,59(5):e5016
The use of mass spectrometry (MS) to acquire molecular images of biological tissues and other substrates has developed into an indispensable analytical tool over the past 25 years. Imaging mass spectrometry technologies are widely used today to study the in situ spatial distributions for a variety of analytes. Early MS images were acquired using secondary ion mass spectrometry and matrix-assisted laser desorption/ionization. Researchers have also designed and developed other ionization techniques in recent years to probe surfaces and generate MS images, including desorption electrospray ionization (DESI), nanoDESI, laser ablation electrospray ionization, and infrared matrix-assisted laser desorption electrospray ionization. Investigators now have a plethora of ionization techniques to select from when performing imaging mass spectrometry experiments. This brief perspective will highlight the utility and relative figures of merit of these techniques within the context of their use in imaging mass spectrometry. 相似文献