An HPLC method with UV and electrospray ionization - mass spectrometry (ESI-MS) detection was developed for the separation and determination of obeticholic acid (OBE) and its related compounds in development process and quality control. OBE and its related compounds were classified into three major group based on the mass spectra profiles: (A) those containing a hydroxyl group at position 3 and 7, (B) those containing a hydroxyl group and/or carbonyl group at position 3, hydrogen, ethyl or ethylidene group at position 6 and a hydroxyl group and/or carbonyl group at position 7, and (C) those containing carbonyl groups at position 3 and 7. ESI-MS ionization of OBE and its related compounds often produced intense adduct ions [M+H+98]+ and/or [M+H+196]+ that were identified as the adduct ions of phosphoric acid ([M+H+H3PO4]+ and [M+H+2H3PO4]+) originating from the mobile phase. The separation on HPLC system was accomplished using stationary phase based on XSelect CSH C18 (3.0×150mm×2.5μm) and a linear gradient elution using acetonitrile and 0.05% of o-phosphoric acid. The condition of chromatographic system was set as follows: flow rate 0.7mL/min, temperature 45°C and UV detection at 192nm. The separation of the 19 compounds was finished in less than 18min (including equilibration time). The HPLC/UV method was partially validated according to International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines in terms of repeatability, selectivity, linearity and limit of quantification and detection.
- MeSH
- chemická frakcionace přístrojové vybavení metody MeSH
- chemie farmaceutická metody MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení metody MeSH
- kontaminace léku prevence a kontrola MeSH
- kyselina chenodeoxycholová analogy a deriváty analýza chemie MeSH
- limita detekce MeSH
- příprava léků přístrojové vybavení metody MeSH
- reprodukovatelnost výsledků MeSH
- řízení kvality * MeSH
- senzitivita a specificita MeSH
- spektrofotometrie ultrafialová přístrojové vybavení metody MeSH
- vysokoúčinná kapalinová chromatografie přístrojové vybavení metody MeSH
- Publikační typ
- časopisecké články MeSH
- validační studie MeSH
This review focuses on the latest development of microseparation electromigration methods in capillaries and microfluidic devices coupled with MS for detection and identification of important analytes. It is a continuation of the review article on the same topic by Kleparnik (Electrophoresis 2015, 36, 159-178). A wide selection of 161 relevant articles covers the literature published from June 2014 till May 2016. New improvements in the instrumentation and methodology of MS interfaced with capillary or microfluidic versions of zone electrophoresis, isotachophoresis, and isoelectric focusing are described in detail. The most frequently implemented MS ionization methods include electrospray ionization, matrix-assisted desorption/ionization and inductively coupled plasma ionization. Although the main attention is paid to the development of instrumentation and methodology, representative examples illustrate also applications in the proteomics, glycomics, metabolomics, biomarker research, forensics, pharmacology, food analysis, and single-cell analysis. The combinations of MS with capillary versions of electrochromatography, and micellar electrokinetic chromatography are not included.
- MeSH
- analýza jednotlivých buněk metody MeSH
- analýza potravin metody MeSH
- biologické markery analýza MeSH
- buněčné linie MeSH
- chromatografie metody MeSH
- elektroforéza kapilární přístrojové vybavení metody MeSH
- glykomika MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení metody MeSH
- hmotnostní spektrometrie metody MeSH
- isoelektrická fokusace přístrojové vybavení metody MeSH
- laboratoř na čipu * MeSH
- lidé MeSH
- metabolomika metody MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice přístrojové vybavení metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
We report a construction of a self-aligning subatmospheric hybrid liquid junction electrospray interface for CE eliminating the need for manual adjustment by guiding the capillaries in a microfabricated liquid junction glass chip at a defined angle. Both the ESI and separation capillaries are inserted into the microfabricated part until their ends touch. The distance between the capillary openings is defined by the angle between the capillaries. The microfabricated part contains channels for placement of the capillaries and connection of the external electrode reservoirs. It was fabricated using standard photolithographic/wet chemical etching techniques followed by thermal bonding. The liquid junction is connected to a subatmospheric electrospray chamber inducing the flow inside the ESI needle and helping the ion transport via aerodynamic focusing.
- MeSH
- design vybavení MeSH
- dextrany MeSH
- elektroforéza kapilární přístrojové vybavení MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení MeSH
- mikrofluidní analytické techniky přístrojové vybavení MeSH
- peptidy MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The capability of employing synthesized zwitterionic silica-based monolithic capillary columns (140 mm × 0.1mm) for separation of highly polar and hydrophilic nucleobases, nucleosides, and nucleotides in hydrophilic interaction chromatography is reported. The suitability of the columns for on-line conjunction with electrospray tandem mass spectrometry was explored. Our results show that the grafted layer of zwitterionic monomer ([2-(methacryloyloxy)ethyl]-dimethyl-(3-sulfopropyl)-ammonium hydroxide or 2-methacryloyloxyethyl phosphorylcholine) on the silica monolithic surface significantly improved the separation selectivity and reproducibility, as compared to the bare silica monolith. The stepwise elution from 90% to 70% of acetonitrile enabled separation of a complex sample mixture containing 21 compounds with a total analysis time less than 40 min.
- MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení metody MeSH
- hydrofobní a hydrofilní interakce MeSH
- nukleosidy chemie izolace a purifikace MeSH
- nukleotidy chemie izolace a purifikace MeSH
- oxid křemičitý chemie MeSH
- povrchové vlastnosti MeSH
- reprodukovatelnost výsledků MeSH
- tandemová hmotnostní spektrometrie přístrojové vybavení metody MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Capillary electrophoresis hyphenated with electrospray mass spectrometry (CE-ESI-MS) has emerged in the past decade as one of the most powerful bioanalytical techniques. As the sensitivity and efficiency of new CE-ESI-MS interface designs are continuously improving, numerical modeling can play important role during their development. In this review, different aspects of computer modeling and simulation of CE-ESI-MS interfaces are comprehensively discussed. Relevant essentials of hydrodynamics as well as state-of-the-art modeling techniques are critically evaluated. Sheath liquid-, sheathless-, and liquid-junction interfaces are reviewed from the viewpoint of multidisciplinary numerical modeling along with details of single and multiphase models together with electric field mediated flows, electrohydrodynamics, and free fluid-surface methods. Practical examples are given to help non-specialists to understand the basic principles and applications. Finally, alternative approaches like air amplifiers are also included. © 2014 Wiley Periodicals, Inc. Mass Spec Rev 34: 558-569, 2015.
- MeSH
- algoritmy MeSH
- chemické modely MeSH
- elektroforéza kapilární přístrojové vybavení metody MeSH
- elektromagnetická pole MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení metody MeSH
- hydrodynamika MeSH
- lidé MeSH
- počítačová simulace MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
DART (direct analysis in real time), a novel technique with wide potential for rapid screening analysis, coupled with high-resolution time-of-flight mass spectrometry (TOF-MS) has been used for quantitative analysis of 5-hydroxymethylfurfural (5-HMF), a typical temperature marker of food. The DART/TOF-MS method was optimised and validated. Quantification of 5-HMF was achieved by use of a stable isotope-labelled 5-HMF standard prepared from glucose. Formation of 5-HMF from saccharides, a potential source of overestimation of results, was evaluated. Forty-four real samples (honey and caramelised condensed sweetened milk) and 50 model samples of heated honey were analysed. The possibility of using DART for analysis of heated samples of honey was confirmed. HPLC and DART/TOF-MS methods for determination of 5-HMF were compared. The correlation equation between these methods was DART = 1.0287HPLC + 0.21340, R(2) = 0.9557. The DART/TOF-MS method has been proved to enable efficient and rapid determination of 5-HMF in a variety of food matrices, for example honey and caramel.
- MeSH
- 2-furaldehyd analogy a deriváty analýza MeSH
- analýza selhání vybavení MeSH
- design vybavení MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení metody MeSH
- počítačové systémy MeSH
- reprodukovatelnost výsledků MeSH
- senzitivita a specificita MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A new method for the simultaneous separation of cocaine and four metabolites in urine by CE-ESI-MS via a pressurized nanoliquid junction interface was developed. The resolution of cocaine, cocaethylene, benzoylecgonine, norcocaine, and ecgonine methyl ester was achieved in a polyvinyl-alcohol-coated capillary with 75 μm id × 50 cm total length, using a 15 mM ammonium formate electrolyte solution (pH 9.5) in less than 15 min. In addition, to enhance sensitivity, a field-amplified sample injection (FASI) was evaluated in terms of injection time and sample solvent composition. The limits of detection achieved with the FASI method ranged from 1.5 to 10 ng/mL for all the compounds. The detection of the studied compounds was performed using an ion-trap mass spectrometer in a positive ionization mode. A mixture of methanol:water (80:20 v/v) containing 0.1% v/v of formic acid was employed as spray liquid and delivered at ~200 nL/min. Under optimal CE-MS conditions, linearity was assessed in the concentration range of interest for all analytes with correlation coefficients r² ≥ 0.9913. Intra- and inter-day precision provided a relative standard deviation lower than 1.54% for migration times and lower than 12.15% for peak areas. Finally, urine samples, spiked with the standard mixture, were extracted using a solid-phase extraction procedure and injected under FASI conditions, providing recoveries from 80% to 94% for all analytes.
- MeSH
- elektroforéza kapilární přístrojové vybavení metody MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení metody MeSH
- kokain metabolismus moč MeSH
- koncentrace vodíkových iontů MeSH
- lidé MeSH
- nanotechnologie přístrojové vybavení metody MeSH
- reprodukovatelnost výsledků MeSH
- senzitivita a specificita MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This review describes the current state of mass spectrometry imaging (MSI) in life sciences. A brief overview of mass spectrometry principles is presented followed by a thorough introduction to the MSI workflows, principles and areas of application. Three major desorption-ionization techniques used in MSI, namely, secondary ion mass spectrometry (SIMS), matrix-assisted laser desorption ionization (MALDI), and desorption electrospray ionization (DESI) are described, and biomedical and life science imaging applications of each ionization technique are reviewed. A separate section is devoted to data handling and current challenges and future perspectives are briefly discussed at the end.
- MeSH
- biologické vědy metody MeSH
- biomedicínský výzkum metody MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení metody MeSH
- lidé MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice přístrojové vybavení metody MeSH
- spektrometrie hmotnostní sekundárních iontů přístrojové vybavení metody MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Capillary isotachophoresis with coupled columns provides efficient means for rapid electrophoretic analysis of sample volumes of up to 10microl or more. Commercially available instruments are commonly equipped with conductivity and UV absorbance detectors; however, their on-line coupling with electrospray mass spectrometry is highly desirable. In this work we have modified the commercial coupled column isotachophoresis system for direct connection to an ion trap mass spectrometer. The design included attachment of an elution block with a short capillary transfer line directing the separated zones towards the mass spectrometer. The modification further included separation of the injection and electrode blocks from the separation columns by semipermeable membranes eliminating unwanted fluid movements in the wide bore fluoropolymer separation capillaries. Fused silica capillaries with varying internal diameter were connected as a transfer line between the elution block and mass spectrometer. The transfer line served also as the ESI tip of the sheathless electrospray interface. During the analysis the first, wide bore preseparation capillary with 0.8mm internal diameter served for removal of the bulk sample components and preseparation of the potentially interfering analytes. After the electronic column switching the separation was finished in a 0.3mm internal diameter capillary and the separated ITP zones were transferred in-line by a spray liquid towards the mass spectrometer. The instrumentation was tested for determination of vitamins in whole blood analysis and separation of tryptic peptides.
Collection of exhaled breath condensate (EBC) is a relatively simple noninvasive method of breath analysis; however, no data have been reported that would relate concentration of volatile compounds in EBC to their gaseous concentrations in exhaled air. The aim of the study was to investigate which volatile compounds are present in EBC and how their concentrations relate to results of direct breath analysis. Thus, samples of EBC were collected in a standard way from several subjects and absolute levels of several common volatile breath metabolites (ammonia, acetone, ethanol, methanol, propanol, isoprene, hydrogen cyanide, formaldehyde and acetaldehyde) were then determined in their headspace using selected ion flow tube mass spectrometry (SIFT-MS). Results are compared with those from on-line breath analyses carried out immediately before collecting the EBC samples. It has been demonstrated that SIFT-MS can be used to quantify the concentrations of volatiles in EBC samples and that, for methanol, ammonia, ethanol and acetone, the EBC concentrations correlate with the direct breath levels. However, the EBC concentrations of isoprene, formaldehyde, acetaldehyde, hydrogen cyanide and propanol do not correlate with direct breath measurements. Copyright (c) 2008 John Wiley & Sons, Ltd.
- MeSH
- analýza selhání vybavení MeSH
- aromatické uhlovodíky analýza MeSH
- dechové testy metody přístrojové vybavení MeSH
- design vybavení MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací metody přístrojové vybavení MeSH
- lidé MeSH
- odběr biologického vzorku metody přístrojové vybavení MeSH
- průtoková injekční analýza metody přístrojové vybavení MeSH
- reprodukovatelnost výsledků MeSH
- senzitivita a specificita MeSH
- volatilizace MeSH
- Check Tag
- lidé MeSH
