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1.
This review focuses on possible pitfalls in hair testing procedures. Knowledge of such pitfalls is useful when developing
and validating methods, since it can be used to avoid wrong results as well as wrong interpretations of correct results. In
recent years, remarkable advances in sensitive and specific analytical techniques have enabled the analysis of drugs in alternative
biological specimens such as hair. Modern analytical procedures for the determination of drugs in hair specimens—mainly by
gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–mass spectrometry (LC–MS)—are reviewed and critically
discussed. Many tables containing information related to this topic are provided. 相似文献
2.
Fekete A Frommberger M Rothballer M Li X Englmann M Fekete J Hartmann A Eberl L Schmitt-Kopplin P 《Analytical and bioanalytical chemistry》2007,387(2):455-467
N-Acylated homoserine lactones (AHLs) are produced by Gram-negative bacteria as communication signals and are frequently studied
as mediators of the “quorum sensing” response of bacterial communities. Several reports have recently been published on the
identification of AHLs from different species and attempts have been made to study their role in natural habitats, for example
the surface of plant roots in the rhizosphere. In this article, different analytical methods, including bacterial biosensors
and chromatographic techniques, are reviewed. A concept for assignment of the structures of AHLs is also presented. The retention
behaviour of derivatives of AHLs containing β-keto or hydroxyl groups and/or double bonds has been evaluated in relation to
the separation behaviour of AHLs with saturated and unsubstituted alkanoyl chains. Samples have also been analysed by high
resolution mass spectrometry (Fourier-transform ion-cyclotron-resonance mass spectrometry, FTICR-MS), nano liquid chromatography–electrospray
ionization ion trap mass spectrometry (nano-LC–MS) and by the aid of a biosensor. The results obtained from ultra performance
liquid chromatography (UPLC), FTICR-MS, nano-LC–MS, and bioassays have been compared to attempt structural characterisation
of AHL without chemical synthesis of analytical standards. The method was used to identify the major AHL compound produced
by the rhizosphere bacterium Acidovorax sp. N35 as N-(3-hydroxydecanoyl)homoserine lactone. 相似文献
3.
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
4.
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
5.
Current role of LC–MS(/MS) in doping control 总被引:1,自引:0,他引:1
Liquid chromatography–(tandem) mass spectrometry (LC–MS/MS) has revolutionized the detection assays used in doping control
analysis over the last decade. New methods have enabled the determination of drugs that were formerly difficult to detect
or undetectable at preceding sample concentrations, and complex and/or time-consuming procedures based on alternative chromatographic–mass
spectrometric or immunochemical principles have been replaced by faster, more comprehensive and robust assays. A critical
overview of the contributions of LC–MS(/MS) to sports drug testing is provided, including recent developments regarding low
and high molecular weight drugs. 相似文献
6.
Mol HG Rooseboom A van Dam R Roding M Arondeus K Sunarto S 《Analytical and bioanalytical chemistry》2007,389(6):1715-1754
The ethyl acetate-based multi-residue method for determination of pesticide residues in produce has been modified for gas
chromatographic (GC) analysis by implementation of dispersive solid-phase extraction (using primary–secondary amine and graphitized
carbon black) and large-volume (20 μL) injection. The same extract, before clean-up and after a change of solvent, was also
analyzed by liquid chromatography with tandem mass spectrometry (LC–MS–MS). All aspects related to sample preparation were
re-assessed with regard to ease and speed of the analysis. The principle of the extraction procedure (solvent, salt) was not
changed, to avoid the possibility invalidating data acquired over past decades. The modifications were made with techniques
currently commonly applied in routine laboratories, GC–MS and LC–MS–MS, in mind. The modified method enables processing (from
homogenization until final extracts for both GC and LC) of 30 samples per eight hours per person. Limits of quantification
(LOQs) of 0.01 mg kg−1 were achieved with both GC–MS (full-scan acquisition, 10 mg matrix equivalent injected) and LC–MS–MS (2 mg injected) for
most of the pesticides. Validation data for 341 pesticides and degradation products are presented. A compilation of analytical
quality-control data for pesticides routinely analyzed by GC–MS (135 compounds) and LC–MS–MS (136 compounds) in over 100 different
matrices, obtained over a period of 15 months, are also presented and discussed. At the 0.05 mg kg−1 level acceptable recoveries were obtained for 93% (GC–MS) and 92% (LC–MS–MS) of pesticide–matrix combinations. 相似文献
7.
Sogawa K Watanabe M Sato K Segawa S Ishii C Miyabe A Murata S Saito T Nomura F 《Analytical and bioanalytical chemistry》2011,400(7):1905-1911
In a clinical diagnosis microbiology laboratory, the current method of identifying bacterial isolates is based mainly on phenotypic
characteristics, for example growth pattern on different media, colony morphology, Gram stain, and various biochemical reactions.
These techniques collectively enable great accuracy in identifying most bacterial isolates, but are costly and time-consuming.
In our clinical microbiology laboratory, we prospectively assessed the ability of matrix-assisted laser desorption ionization–time
of flight mass spectrometry (MALDI–TOF MS) to identify bacterial strains that were routinely isolated from clinical samples.
Bacterial colonies obtained from a total of 468 strains of 92 bacterial species isolated at the Department of Clinical Laboratory
at Chiba University were directly placed on target MALDI plates followed by addition of CHCA matrix solution. The plates were
then subjected to MALDI–TOF MS measurement and the microorganisms were identified by pattern matching with the libraries in
the BioTyper 2.0 software. Identification success at the species and genus levels was 91.7% (429/468) and 97.0% (454/468),
respectively. MALDI–TOF MS is a rapid, simple, and high-throughput proteomic technique for identification of a variety of
bacterial species. Because colony-to-colony differences and effects of culture duration on the results are minimal, it can
be implemented in a conventional laboratory setting. Although for some pathogens, preanalytical processes should be refined,
and the current database should be improved to obtain more accurate results, the MALDI–TOF MS based method performs, in general,
as well as conventional methods and is a promising technology in clinical laboratories. 相似文献
8.
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
9.
Clinical and forensic toxicology and doping control deal with hundreds or thousands of drugs that may cause poisoning or are
abused, are illicit, or are prohibited in sports. Rapid and reliable screening for all these compounds of different chemical
and pharmaceutical nature, preferably in a single analytical method, is a substantial effort for analytical toxicologists.
Combined chromatography–mass spectrometry techniques with standardised reference libraries have been most commonly used for
the purpose. In the last ten years, the focus has shifted from gas chromatography–mass spectrometry to liquid chromatography–mass
spectrometry, because of progress in instrument technology and partly because of the polarity and low volatility of many new
relevant substances. High-resolution mass spectrometry (HRMS), which enables accurate mass measurement at high resolving power,
has recently evolved to the stage that is rapidly causing a shift from unit-resolution, quadrupole-dominated instrumentation.
The main HRMS techniques today are time-of-flight mass spectrometry and Orbitrap Fourier-transform mass spectrometry. Both
techniques enable a range of different drug-screening strategies that essentially rely on measuring a compound’s or a fragment’s
mass with sufficiently high accuracy that its elemental composition can be determined directly. Accurate mass and isotopic
pattern acts as a filter for confirming the identity of a compound or even identification of an unknown. High mass resolution
is essential for improving confidence in accurate mass results in the analysis of complex biological samples. This review
discusses recent applications of HRMS in analytical toxicology. 相似文献
10.
Krystyna Srogi 《Mikrochimica acta》2006,154(3-4):191-212
This article reviews the analysis of drugs and drug metabolites in hair by chromatographic procedures, including the pretreatment
steps, and the extraction methods. The general tendency in the last years, to highly sophisticated techniques (GC–MS–NCI,
HPLC–MS, GC–MS–MS) illustrates the constant fight for sensitivity. 相似文献
11.
Environmental analysis of fluorinated alkyl substances by liquid chromatography–(tandem) mass spectrometry: a review 总被引:1,自引:0,他引:1
Fluorinated alkyl substances (FASs) are widely distributed contaminants that have been found in many environmental, human
and biological samples throughout the world. Perfluorochemicals are used in many industry and consumer products, such as polymers
and surfactants, because they have unique and useful properties (they are stable, chemically inert and generally unreactive).
However, these compounds have also been found to be toxic, persistent and bioaccumulative. In recent years various analytical
methods have been developed for the analysis of FASs in environmental samples. Most of these methods are based on liquid chromatography
coupled to mass spectrometry (LC–MS) or tandem mass spectrometry (LC–MS/MS), since this is considered to be the technique
of choice. This article reviews the various LC–(tandem)MS methods described so far for the analysis of FASs in water, sediment,
sludge and biota samples. It discusses the main experimental conditions used for sample pretreatment and for analysis as well
as the most relevant problems encountered and the limits of detection achieved. 相似文献
12.
Two techniques based on analytical pyrolysis and mass spectrometry, direct exposure-MS (DE-MS) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), were used to characterise waterlogged archaeological wood and to study degradation patterns of wood in aqueous environments. The two techniques were applied to samples from the excavation of the Site of the Ancient Ships of Pisa San Rossore in Pisa (Italy), and data were compared to those relative to native sound wood of the same species (pine, elm, beech). Both the methods result valuable in the analysis of ancient wood artefacts, avoiding the long wet-chemical procedures that are commonly used in wood analysis, and allowing us to use a minimal sample size. DE-MS achieves a global mass spectral fingerprint of lignin and polysaccharides pyrolysis compounds in few minutes, and the results have been interpreted with the support of principal component analysis (PCA) of mass spectra. Py-GC/MS permits detailed molecular analysis of pyrolysis compounds and highlights some chemical modifications of lignin in archaeological samples, as demethylation of both guaiacyl and syringyl lignin units. Both the techniques demonstrate consistent loss of polysaccharides in archaeological wood. 相似文献
13.
Deventer K Roels K Delbeke FT Van Eenoo P 《Analytical and bioanalytical chemistry》2011,401(2):421-432
This paper reviews the prevalence of legal and illegal stimulants in relation to doping-control analysis. Stimulants are among
the oldest classes of doping agents, having been used since ancient times. Despite the ease with which they can be detected
and the availability of sensitive detection methods, stimulants are still popular among athletes. Indeed, they remain one
of the top three most popular classes of prohibited substances. Because the list of legal and illegal stimulants is extensive
only a selection is discussed in detail. The compounds selected are caffeine, ephedrines, amphetamine and related compounds,
methylphenidate, cocaine, strychnine, modafinil, adrafinil, 4-methyl-2-hexaneamine, and sibutramine. These compounds are mainly
prevalent in sport or are of therapeutic importance. Because stimulants are the oldest doping class the first detection methods
were for this group. Several early detection techniques including GC–NPD, GC–ECD, and TLC are highlighted. The more novel
detection techniques GC–MS and LC–MS are also discussed in detail. In particular, the last technique has been shown to enable
successful detection of stimulants difficult to detect by GC–MS or for stimulants previously undetectable. Because stimulants
are also regularly detected in nutritional (food) supplements a section on this topic is also included. 相似文献
14.
Residual antimicrobials in food constitute a risk to human health. Although epidemiological data on the real magnitude of
their adverse effects are very scarce, they indicate that food could be an important vehicle for evolution and dissemination
of antimicrobial-resistant bacteria. Public health agencies in many countries rely on detection by mass spectrometry (MS)
for unambiguous identification of residues of antimicrobial agents in animal food products for human consumption. The introduction
of relatively inexpensive and robust liquid chromatography (LC)–MS systems has given a strong impulse to the development of
confirmatory methods for the above medicines in foodstuffs. The initial part of this review, after a brief introduction into
the field of antimicrobials, is dedicated to the most important EU regulations and directives for control of residues of these
substances in animal products. The main attention in this review is on the sample-treatment and MS detection systems in use
today for analysing the most important classes of antimicrobials in various biological matrices (milk, animal tissues, eggs,
and honey). As evidenced by this review, reversed-phase LC combined with tandem MS, usually triple-quadrupole MS (QqQMS),
is currently the preferred technique in most residue analysis of a single-class of antimicrobials. A recently emerging analytical
strategy is that of developing methods for detecting a large variety of veterinary drugs belonging to different classes, including
pesticides (multi-class residue analysis). To do this, simple and generic extraction and separation techniques applicable
to a broad range of compounds differing in physical and chemical properties have been adopted. Such methods are still based
mainly on LC–QqQMS. Emerging alternative MS detection systems are time-of-flight MS, which provides accurate mass of the analyte(s),
or Q–linear ion trap (IT) MS that eliminates some limitations of ITMS
n
. 相似文献
15.
Zeisler R Paul RL Oflaz Spatz R Yu LL Mann JL Kelly WR Lang BE Leigh SD Fagan J 《Analytical and bioanalytical chemistry》2011,399(1):509-517
A material containing single-wall carbon nanotubes (SWCNTs) with other carbon species, catalyst residues, and trace element
contaminants has been prepared by the National Institute of Standards and Technology for characterization and distribution
as Standard Reference Material SRM 2483 Carbon Nanotube Soot. Neutron activation analysis (NAA) and inductively coupled plasma
mass spectrometry (ICP–MS) were selected to characterize the elemental composition. Catalyst residues at percentage mass fraction
level were determined with independent NAA procedures and a number of trace elements, including selected rare earth elements,
were determined with NAA and ICP–MS procedures. The results of the investigated materials agreed well among the NAA and ICP–MS
procedures and good agreement of measured values with certified values was found in selected SRMs included in the analyses.
Based on this work mass fraction values for catalyst and trace elements were assigned to the candidate SRM. 相似文献
16.
E. Pitarch T. Portolés J. M. Marín M. Ibáñez F. Albarrán F. Hernández 《Analytical and bioanalytical chemistry》2010,397(7):2763-2776
The presence of a wide variety of organic pollutants with different physicochemical characteristics has been investigated
in wastewater samples from a municipal solid-waste-treatment plant in Castellón, Spain. An advanced analytical strategy was
applied—combined used of two powerful and complementary techniques, GC and LC, both hyphenated with tandem mass spectrometry
with triple-quadrupole analyzers. The GC–MS–MS method was based on sample extraction using C18 SPE cartridges and enabled the determination of approximately 60 compounds from different chemical families, for example
PAHs, octyl/nonylphenols, PCBs, organochlorine compounds, insecticides, herbicides, and PBDEs. Most of the compounds selected
are included as priority contaminants in the European Union (EU) Water Directive. The UHPLC–MS–MS method, which provided high
chromatographic resolution and sensitivity and short analysis time, used sample extraction with Oasis HLB SPE cartridges and
enabled the determination of 37 (more polar) pesticides. The methodology developed was applied to the analysis of 41 water
samples (20 untreated raw leachates and 21 treated samples) collected between March 2007 and February 2009. Amounts of the
contaminants investigated rarely exceeded 0.5 μg L−1 in the treated (reverse osmosis) water samples analyzed. As expected, in untreated leachates the number of compounds detected
and the concentrations found were notably higher than in treated waters. The most commonly detected pollutants were herbicides
(simazine, terbuthylazine, terbutryn, terbumeton, terbacil, and diuron), fungicides (thiabendazole and carbendazim), and 4-t-octylphenol. The results obtained proved that use of reverse osmosis for water treatment was efficient and notably reduced
the amounts of organic contaminants found in raw leachate samples. In order to investigate the presence of other non-target
contaminants, water samples were also analyzed by using GC–TOF MS and LC–QTOF MS. Several organic pollutants that did not
form a part of the previous list of target contaminants were identified in the samples, because of the high sensitivity of
TOF MS in full-spectrum acquisition mode and the valuable accurate-mass information provided by these instruments. The insecticide
diazinon, the fungicide diphenylamide, the UV filter benzophenone, N-butylbenzenesulfonamide (N-BBSA), the insect repellent diethyltoluamide, caffeine, and the pharmaceuticals erythromycin,
benzenesulfonanilide, ibuprofen, atenolol, and paracetamol were some of the compounds identified in the water samples analyzed. 相似文献
17.
B. Debrus J. Broséus D. Guillarme P. Lebrun P. Hubert J.-L. Veuthey P. Esseiva S. Rudaz 《Analytical and bioanalytical chemistry》2011,399(8):2719-2730
Nowadays, in forensic laboratories, heroin profiling is frequently carried out by gas chromatography coupled with mass spectrometry
(GC-MS). This analytical technique is well established, provides good sensitivity and reproducibility, and allows the use
of large databases. Despite those benefits, recently introduced analytical techniques, such as ultra-high-pressure liquid
chromatography (UHPLC), could offer better chromatographic performance, which needs to be considered to increase the analysis
throughput for heroin profiling. With the latter, chromatographic conditions were optimized through commercial modeling software
and two atmospheric pressure ionization sources were evaluated. Data obtained from UHPLC–MS/MS were thus transferred, thanks
to mathematical models to mimic GC-MS data. A calibration and a validation set of representative heroin samples were selected
among the database to establish a transfer methodology and assess the models’ abilities to transfer using principal component
analysis and hierarchical classification analysis. These abilities were evaluated by computing the frequency of successful
classification of UHPLC–MS/MS data among GC-MS database. Seven mathematical models were tested to adjust UHPLC–MS/MS data
to GC-MS data. A simplified mathematical model was finally selected and offered a frequency of successful transfer equal to
95%. 相似文献
18.
The context of validation for mass spectrometry (MS)-based methods is critically analysed. The focus is on the fitness for
purpose depending on the task of the method. Information is given on commonly accepted procedures for the implementation and
acceptance of analytical methods as ‘confirmatory methods’ according to EU criteria, and strategies for measurement. Attention
is paid to the problem of matrix effects in the case of liquid chromatography-mass spectrometry-based procedures, since according
to recent guidelines for bioanalytical method validations, there is a need to evaluate matrix effects during development and
validation of LC-MS methods “to ensure that precision, selectivity and sensitivity will not be compromised”. Beneficial aspects
of the qualification process to ensure the suitability of the MS analytical system are also evaluated and discussed. 相似文献
19.
Beltran J Serrano E López FJ Peruga A Valcarcel M Rosello S 《Analytical and bioanalytical chemistry》2006,385(7):1255-1264
Two analytical procedures, one based on purge-and-trap and the other on solid phase microextraction, both followed by GC–MS
measurement using an ion-trap mass spectrometer in the electron impact mode, have been developed for determination and quantitation
of up to 39 aroma compounds in fresh tomatoes. The method based on purge-and-trap for isolation of the volatile compounds
uses Tenax as adsorbent and a hexane–diethyl ether mixture as solvent for elution. The method was validated for linearity,
precision (better than 20% for most compounds), and limit of detection, which was approximately 1 ng g−1. This method enabled identification of up to 30 compounds in real samples. Use of SPME was considered as an alternative,
to simplify sample treatment while maintaining the information level for the samples (e.g. the number of compounds detected)
and quality of quantitation. A procedure based on SPME using a Carboxen/polydimethylsiloxane fibre was developed and validated
for determination of 29 aroma compounds; precision was better than 20% and limits of detection ranged from 4 to 30 ng g−1. 相似文献
20.
Jörg Bettmer 《Analytical and bioanalytical chemistry》2010,397(8):3495-3502
ICP–MS techniques based on isotope dilution analysis can be regarded as an emerging tool in quantitative protein analysis.
Well-known concepts, for example species-specific and unspecific isotope dilution analysis, which promoted accurate and precise
quantification in elemental speciation studies, have nowadays been transferred to the analysis of large biomolecules, e.g.
proteins. Besides detection of heteroatom-containing proteins, the artificial introduction of metal-containing labels has
attracted much attention and, as a consequence, ICP–MS-based isotope dilution techniques can serve as a valuable quantification
tool. In particular, because isotope dilution ICP–MS techniques can enable absolute protein quantification, they can be regarded
as an attractive technique in current and prospective proteomics. In this review, recent developments and applications will
be highlighted and critically assessed. 相似文献