Coupling of capillary electrophoresis (CE) with mass spectrometry (MS) represents a powerful combination for performing rapid, efficient, and sensitive analysis of a variety of compounds. Here we describe a construction, operation, and application of a microfabricated liquid junction CE-MS interface. The interface is designed as a microfabricated unit with an integrated liquid junction and electrospray tip made from polyimide, which is positioned in a plastic connection block securing the separation CE capillary and attachable to the CE instrument. The application was demonstrated by CE-MS analysis of dextran oligomers labeled by (2-aminoethyl)trimethylammonium (AETMA) salt.

• Klíčová slova
• CE-MS interface, Capillary electrophoresis, Liquid junction, Mass spectrometry,
• MeSH
• elektroforéza kapilární * metody   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací * MeSH
• hmotnostní spektrometrie metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Cheeses are a group of fermented dairy products that are produced all over the world in various forms and flavours. Milk, especially sheep or goat milk, is still regarded as an expensive raw material in the world, which makes milk and milk products highly attractive as a fraud target. Most often, such fraud includes partial or complete substitution with cheaper sorts of milk (e.g. bovine milk). The aim of this work was to verify the authenticity of 27 cheeses commonly emerging on the Czech food market. The cheeses were distinguished on the basis of milk animal species origin. For this purpose, two mass spectrometry techniques were used: matrix-assisted laser desorption/ionization with time of flight mass spectrometry together with principal component analysis method and liquid chromatography coupled with electrospray ionization and quadrupole time-of-flight mass spectrometry. The results were a partial success, because the cheeses could only be partially distinguished with the first mass spectrometry technique probably because of the influence of some protein additive materials in cheeses. The second technique allowed for collecting higher quality results and thus appears to be highly suitable for the research task.

• Klíčová slova
• casein, cheese, mass spectrometry, milk,
• MeSH
• chromatografie kapalinová MeSH
• kaseiny chemie   MeSH
• mléko chemie   MeSH
• skot MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• sýr analýza   MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kaseiny MeSH

Siderophores play important roles in microbial iron piracy, and are applied as infectious disease biomarkers and novel pharmaceutical drugs. Inductively coupled plasma and molecular mass spectrometry (ICP-MS) combined with high resolution separations allow characterization of siderophores in complex samples taking advantages of mass defect data filtering, tandem mass spectrometry, and iron-containing compound quantitation. The enrichment approaches used in siderophore analysis and current ICP-MS technologies are reviewed. The recent tools for fast dereplication of secondary metabolites and their databases are reported. This review on siderophores is concluded with their recent medical, biochemical, geochemical, and agricultural applications in mass spectrometry context.

• Klíčová slova
• biomarkers, dereplication, iron, mass spectrometry, siderophores,
• MeSH
• antibiotická rezistence MeSH
• biodegradace MeSH
• chelátory farmakologie   MeSH
• hmotnostní spektrometrie metody   MeSH
• mikrobiální testy citlivosti MeSH
• sekundární metabolismus MeSH
• siderofory analýza   chemie   metabolismus   farmakologie   MeSH
• spektrofotometrie atomová metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• chelátory MeSH
• siderofory MeSH

RATIONALE: It has been proposed that malondialdehyde (MDA) reflects free oxygen-radical lipid peroxidation and can be useful as a biomarker to track this process. For the analysis of MDA molecules in humid air by selected ion flow tube mass spectrometry (SIFT-MS), the rate coefficients and the ion product distributions for the reactions of the SIFT-MS reagent ions with volatile MDA in the presence of water vapour are required. METHODS: The SIFT technique has been used to determine the rate coefficients and ion product distributions for the reactions of H3O(+), NO(+) and O2 (+•) with gas-phase MDA. In support of the SIFT-MS analysis of MDA, solid-phase microextraction, SPME, coupled with gas chromatography/mass spectrometry, GC/MS, has been used to confirm the identification of MDA. RESULTS: The primary product ions have been identified for the reactions of H3O(+), NO(+) and O2 (+•) with MDA and the formation of their hydrates formed in humid samples is described. The following combinations of reagent and the analyte ions (given as m/z values) have been adopted for SIFT-MS analyses of MDA in the gas phase: H3O(+): 109; NO(+): 89, 102; O2 (+•): 72, 90, 108, 126. The detection and quantification of MDA released by a cell culture by SIFT-MS are demonstrated. CONCLUSIONS: This detailed study has provided the kinetics data required for the SIFT-MS analysis of MDA in humid air, including exhaled breath and the headspace of liquid-phase biogenic media. The detection and quantification by SIFT-MS of MDA released by a cell culture are demonstrated.

• MeSH
• hmotnostní spektrometrie metody   MeSH
• lidé MeSH
• malondialdehyd chemie   MeSH
• nádorové buněčné linie MeSH
• pára analýza   MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí metody   MeSH
• vlhkost MeSH
• vzduch analýza   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• malondialdehyd MeSH
• pára MeSH

Hydrogen/deuterium exchange (HDX) followed by mass spectrometry detection (MS) provides a fast, reliable, and detailed solution for the assessment of a protein structure. It has been widely recognized as an indispensable tool and already approved by several regulatory agencies as a structural technique for the validation of protein biopharmaceuticals, including antibody-based drugs. Antibodies are of a key importance in life and medical sciences but considered to be challenging analytical targets because of their compact structure stabilized by disulfide bonds and due to the presence of glycosylation. Despite these difficulties, there are already numerous excellent studies describing MS-based antibody structure characterization. In this chapter, we describe a universal HDX-MS workflow. Deeper attention is paid to sample handling, optimization procedures, and feasibility stages, as these elements of the HDX experiment are crucial for obtaining reliable detailed and spatially well-resolved information.

• Klíčová slova
• Antibody, Biosimilars, Hydrogen/deuterium exchange, Mass spectrometry, Protein structure and dynamics, Proteolysis,
• MeSH
• deuterium MeSH
• hmotnostní spektrometrie MeSH
• protilátky * MeSH
• vodík/deuteriová výměna a hmotnostní spektrometrie * MeSH
• vodík MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• deuterium MeSH
• protilátky * MeSH
• vodík MeSH

The soft tick, Ornithodoros moubata, is a vector of several bacterial and viral pathogens including Borrelia duttoni, a causative agent of relapsing fever and African swine fever virus. Previously, a sialic acid-specific lectin Dorin M was isolated from its hemolymph. Here, we report on the complete characterization of the primary sequence of Dorin M. Using liquid chromatography coupled to mass spectrometry, we identified three different glycopeptides in the tryptic digest of Dorin M. The peptide, as well as the glycan part of all glycopeptides, were further fully sequenced by means of tandem mass spectrometry (MS2) and multiple-stage mass spectrometry (MS3). Two classical N-glycosylation sites were modified by high-mannose-type glycans containing up to nine mannose residues. The third site bore a glycan with four to five mannose residues and a deoxyhexose (fucose) attached to the proximal N-acetylglycosamine. The microheterogeneity at each site was estimated based on chromatographic behavior of different glycoforms. The fourth, a non-classical N-glycosylation site (Asn-Asn-Cys), was not glycosylated, probably due to the involvement of the cysteine residue in a disulfide bridge.

• MeSH
• glykopeptidy chemie   MeSH
• glykoproteiny chemie   MeSH
• glykosylace MeSH
• lektiny chemie   MeSH
• molekulární sekvence - údaje MeSH
• Ornithodoros chemie   MeSH
• sekvence aminokyselin MeSH
• tandemová hmotnostní spektrometrie metody   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• glykopeptidy MeSH
• glykoproteiny MeSH
• lektiny MeSH

Monoclonal gammopathies are a group of blood diseases characterized by presence of abnormal immunoglobulins in peripheral blood and/or urine of patients. Multiple myeloma and plasma cell leukemia are monoclonal gammopathies with unclear etiology, caused by malignant transformation of bone marrow plasma cells. Mass spectrometry with matrix-assisted laser desorption/ionization and time-of-flight detection is commonly used for investigation of the peptidome and small proteome of blood plasma with high accuracy, robustness, and cost-effectivity. In addition, mass spectrometry coupled with advanced statistics can be used for molecular profiling, classification, and diagnosis of liquid biopsies and tissue specimens in various malignancies. Despite the fact there have been fully optimized protocols for mass spectrometry of normal blood plasma available for decades, in monoclonal gammopathy patients, the massive alterations of biophysical and biochemical parameters of peripheral blood plasma often limit the mass spectrometry measurements. In this paper, we present a new two-step extraction protocol and demonstrated the enhanced resolution and intensity (>50×) of mass spectra obtained from extracts of peripheral blood plasma from monoclonal gammopathy patients. When coupled with advanced statistics and machine learning, the mass spectra profiles enabled the direct identification, classification, and discrimination of multiple myeloma and plasma cell leukemia patients with high accuracy and precision. A model based on PLS-DA achieved the best performance with 71.5% accuracy (95% confidence interval, CI = 57.1-83.3%) when the 10× repeated 5-fold CV was performed. In summary, the two-step extraction protocol improved the analysis of monoclonal gammopathy peripheral blood plasma samples by mass spectrometry and provided a tool for addressing the complex molecular etiology of monoclonal gammopathies.

• Klíčová slova
• MALDI-TOF mass spectrometry, fingerprinting, machine learning, molecular profiling, monoclonal gammopathy, multiple myeloma, partial least-squares-discriminant analysis, plasma cell leukemia, principal component analysis,
• MeSH
• krevní plazma MeSH
• lidé MeSH
• mnohočetný myelom * diagnóza   MeSH
• paraproteinemie * diagnóza   MeSH
• plazmocelulární leukemie * MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

The series of 14 complex organotin(IV) compounds containing many tin atoms and noncovalent bonds in the structure was characterized by electrospray ionization multistage tandem mass spectrometry (ESI-MS(n)). The mass spectra were measured in both polarity modes to obtain complementary structural information. The characteristic pattern of ten natural tin isotopes allowed the determination of the number of tin atoms in the molecular adducts and fragment ions by comparing theoretical and experimental isotopic distributions. Positive ion ESI spectra show unusual adduct formation depending on the type of organic solvent used for the direct infusion analysis owing to the ion-molecule reactions in the ion source. On the basis of the detailed spectral interpretation of organotin(IV) compounds, the fragmentation patterns of multitin organometallic compounds have been proposed. Noncovalent bonds in polymeric complexes are fragmented first, which is then followed by characteristic neutral losses in monomeric units.

• MeSH
• difrakce rentgenového záření MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• organocínové sloučeniny analýza   MeSH
• organokovové sloučeniny analýza   MeSH
• rozpouštědla MeSH
• tandemová hmotnostní spektrometrie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• organocínové sloučeniny MeSH
• organokovové sloučeniny MeSH
• rozpouštědla MeSH

In recent years, mass spectrometry (MS) has become the dominant technology in lipidomic analysis. It is widely used in diagnosis and research of lipid metabolism disorders including those characterized by impairment of lysosomal functions and storage of nondegraded-degraded substrates. These rare diseases, which include sphingolipidoses, have severe and often fatal clinical consequences. Modern MS methods have contributed significantly to achieve a definitive diagnosis, which is essential in clinical practice to begin properly targeted patient care. Here we summarize MS and tandem MS methods used for qualitative and quantitative analysis of sphingolipids (SL) relative to the diagnostic process for sphingolipidoses and studies focusing on alterations in cell functions due to these disorders. This review covers the following topics: Tandem MS is sensitive and robust in determining the composition of sphingolipid classes in various biological materials. Its ability to establish SL metabolomic profiles using MS bench-top analyzers, significantly benefits the first stages of a diagnosis as well as metabolic studies of these disorders. It can thus contribute to a better understanding of the biological significance of SL.

• Klíčová slova
• Deacylated sphingolipids, Electrospray ionization, Enzymology, Lysosomal storage disorders, Sphingolipidoses, Sphingolipids, Tandem mass spectrometry,
• MeSH
• lidé MeSH
• sfingolipidózy diagnóza   MeSH
• sfingolipidy analýza   chemie   fyziologie   MeSH
• tandemová hmotnostní spektrometrie metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• sfingolipidy MeSH

Microorganisms, plants, and animals alike have specialized acquisition pathways for obtaining metals, with microorganisms and plants biosynthesizing and secreting small molecule natural products called siderophores and metallophores with high affinities and specificities for iron or other non-iron metals, respectively. This chapter details a novel approach to discovering metal-binding molecules, including siderophores and metallophores, from complex samples ranging from microbial supernatants to biological tissue to environmental samples. This approach, called Native Metabolomics, is a mass spectrometry method in which pH adjustment and metal infusion post-liquid chromatography are interfaced with ion identity molecular networking (IIMN). This rule-based data analysis workflow that enables the identification of metal-binding species based on defined mass (m/z) offsets with the same chromatographic profiles and retention times. Ion identity molecular networking connects compounds that are structurally similar by their fragmentation pattern and species that are ion adducts of the same compound by chromatographic shape correlations. This approach has previously revealed new insights into metal binding metabolites, including that yersiniabactin can act as a biological zincophore (in addition to its known role as a siderophore), that the recently elucidated lepotchelin natural products are cyanobacterial metallophores, and that antioxidants in traditional medicine bind iron. Native metabolomics can be conducted on any liquid chromatography-mass spectrometry system to explore the binding of any metal or multiple metals simultaneously, underscoring the potential for this method to become an essential strategy for elucidating biological metal-binding molecules.

• Klíčová slova
• Direct infusion, Metallophore discovery, Native mass spectrometry, Native metabolomics, Natural product discovery, Siderophore discovery,
• MeSH
• chromatografie kapalinová metody   MeSH
• hmotnostní spektrometrie * metody   MeSH
• metabolomika * metody   MeSH
• siderofory * metabolismus   chemie   analýza   MeSH
• železo metabolismus   analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• siderofory * MeSH
• železo MeSH