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1.
J Agric Food Chem ; 68(10): 3121-3131, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32053364

RESUMO

A new method to simultaneously analyze various glucosinolates (GSLs) and isothiocyanates (ITCs) by reversed-phase ultra-high-performance liquid chromatography-electron spray ionization-tandem mass spectrometry has been developed and validated for 14 GSLs and 15 ITCs. It involved derivatization of ITCs with N-acetyl-l-cysteine (NAC). The limits of detection were 0.4-1.6 µM for GSLs and 0.9-2.6 µM for NAC-ITCs. The analysis of Sinapis alba, Brassica napus, and Brassica juncea extracts spiked with 14 GSLs and 15 ITCs indicated that the method generally had good intraday (≤10% RSD) and interday precisions (≤16% RSD). Recovery of the method was unaffected by the extracts and within 71-110% for GSLs and 66-122% for NAC-ITCs. The method was able to monitor the enzymatic hydrolysis of standard GSLs to ITCs in mixtures. Furthermore, GSLs and ITCs were simultaneously determined in Brassicaceae plant extracts before and after myrosinase treatment. This method can be applied to further investigate the enzymatic conversion of GSLs to ITCs in complex mixtures.


Assuntos
Brassicaceae/química , Cromatografia Líquida de Alta Pressão/métodos , Glucosinolatos/química , Isotiocianatos/química , Extratos Vegetais/química , Sinapis/química , Espectrometria de Massas em Tandem/métodos , Cromatografia de Fase Reversa/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos
2.
J Agric Food Chem ; 68(7): 2174-2182, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31985220

RESUMO

Goat milk oligosaccharides are complex carbohydrates with a variety of biological functions. Free oligosaccharides from goat milk show more similarity to human milk than cow milk. At present, changes in goat milk glycoconjugates at different parities remain poorly studied. Herein, we qualitatively and quantitatively compared the goat milk glycoprotein N/O-glycome at different parities using a stable isotope labeling followed by electrospray ionization mass spectrometry and online hydrophilic interaction chromatography. N-Glycans were mainly fucosylated and nonfucosylated nonsialylated, and both fucosylation and sialylation gradually increased with parity, amounting (at the third parity) to 1.25 times and 3.3 times those of the first parity, respectively. O-Glycans were mostly nonfucosylated and nonsialylated, and sialylation increased with increasing parity, and Neu5Ac-sialylated was up to 9 times higher in the third parity than in the first parity, whereas Neu5Gc-sialylated was 5.5 times higher. This study provides a reference for exploring an alternative milk source closest to human milk and for the development of humanized formula milk.


Assuntos
Colostro/química , Polissacarídeos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Feminino , Glicosilação , Cabras , Humanos , Leite Humano/química , Oligossacarídeos/química , Espectrometria de Massas em Tandem
3.
Artigo em Inglês | MEDLINE | ID: mdl-31891858

RESUMO

Gangliosides (GG) are glycosphingolipids, composed of a ceramide moiety (fatty acid and long chain base) linked to an oligosaccharide chain containing one (or more) molecule of sialic acid. After lipid extraction from biological matrices, quantification of GG by liquid chromatography coupled to electrospray ionization mass spectrometry (LC-ESI/MS) can be impacted by ion suppression effects due to co-elution with more abundant lipids in the matrix. In this study, a simple, rapid and efficient method to purify GG from biological samples by Phree columns is proposed. This approach proved to be useful in eliminating phospholipids (PL) from the matrix and thus increasing the signal of GG classes and molecular species in rat brain samples during LC-ESI/MS analysis.


Assuntos
Cromatografia Líquida/métodos , Gangliosídeos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Química Encefálica , Masculino , Ratos , Ratos Wistar
4.
Biosci Biotechnol Biochem ; 84(3): 500-506, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31694479

RESUMO

A liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the separation and quantification of the enantiomers of N-methylaspartate and N-methylglutamate, after derivatization with Nα-(5-fluoro-2,4-dinitrophenyl)-L-leucinamide was established. The time required for the LC-ESI-MS/MS analysis was within 20 min and the detection limit was approximately 10 fmol per injection, demonstrating that this method can be used for the rapid determination of D-aspartate N-methyltransferase activity in the ark shell clam Scapharca broughtonii.Abbreviations: NMDA: N-methyl-D-aspartate; NMLA: N-methyl-L-aspartate; NMDG: N-methyl-D-glutamate; NMLG: N-methyl-L-glutamate; NMA: N-methylaspartate; NMG: N-methylglutamate; HPLC: high-performance liquid chromatography; SAM: S-adenosyl-L-methionine; OPA: o-phthalaldehyde; LC-ESI-MS/MS: liquid chromatography-electrospray ionization-tandem mass spectrometry; FDLA: Nα-(5-fluoro-2,4-dinitrophenyl)-L-leucinamide; FDAA: Nα-(5-fluoro-2,4-dinitrophenyl)-L-alaninamide; ESI: electrospray ionization; LC-ESI-MS: liquid chromatography-electrospray ionization-mass spectrometry; MS/MS: tandem mass spectrometry.


Assuntos
Ácido Aspártico/química , Bivalves/metabolismo , Cromatografia Líquida/métodos , Metiltransferases/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Metiltransferases/química
5.
J Mass Spectrom ; 55(1): e4463, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31671229

RESUMO

Noncovalent interactions between drugs and proteins play significant roles for drug metabolisms and drug discoveries. Mass spectrometry has been a commonly used method for studying noncovalent interactions. However, the harsh ionization process in electrospray ionization mass spectrometry (ESI-MS) is not conducive to the preservation of noncovalent and unstable biomolecular complexes compared with the cold spray ionization mass spectrometry (CSI-MS). A cold spray ionization providing a stable solvation-ionization at low temperature is milder than ESI, which was more suitable for studying noncovalent drug-protein complexes with exact stoichiometries. In this paper, we apply CSI-MS to explore the interactions of ginsenosides toward amyloid-ß-peptide (Aß) and clarify the therapeutic effect of ginsenosides on Alzheimer's disease (AD) at the molecular level for the first time. The interactions of ginsenosides with Aß were performed by CSI-MS and ESI-MS, respectively. The ginsenosides Rg1 bounded to Aß at the stoichiometries of 1:1 to 5:1 could be characterized by CSI-MS, while dehydration products are more readily available by ESI-MS. The binding force depends on the number of glycosyls and the type of ginsenosides. The relative binding affinities were sorted in order as follows: Rg1 ≈ Re > Rd ≈ Rg2 > Rh2, protopanaxatriol by competition experiments, which were supported by molecular docking experiment. CSI-MS is expected to be a more appropriate approach to determine the weak but specific interactions of proteins with other natural products especially polyhydroxy compounds.


Assuntos
Peptídeos beta-Amiloides/química , Ginsenosídeos/química , Simulação de Acoplamento Molecular/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Sítios de Ligação , Ligação Proteica , Sapogeninas/química , Relação Estrutura-Atividade
6.
Biomed Chromatogr ; 34(2): e4746, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31725913

RESUMO

H3B-6545 is a selective ERα covalent antagonist, which has been demonstrated to be effective in anti-tumor. To fully understand its mechanism of action, it is necessary to investigate the in vitro and in vivo metabolic profiles. For in vitro metabolism, H3B-6545 (50 µM) was incubated with the hepatocytes of rat and human for 2 h. For in vivo metabolism H3B-6545 was orally administered to rats at a single dose of 10 mg/kg, and plasma, urine and fecal samples were then collected. All samples were analyzed by using ultra-high performance liquid chromatography combined with linear ion trap-orbitrap tandem mass spectrometry (UHPLC-LTQ-Orbitrap-MS) operated in positive ion mode. The structures of the metabolites were elucidated by comparing their MS and MS2 spectra with those of parent drug. A total of 11 metabolites, including a GSH adduct, were detected and structurally identified. M2, M7 and M8 were further unambiguously identified by using reference standards. Among these metabolites, M1, M5, M7 and M10 were newly found and reported for the first time. The metabolic pathways of H3B-6545 included deamination (M8 and M9), dealkylation (M2, M3 and M10), N-hydroxylation (M6), hydroxylation (M1 and M4), formation of amide derivatives (M5 and M7) and GSH conjugation (G1).


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Indazóis , Piridinas , Espectrometria de Massas em Tandem/métodos , Animais , Células Cultivadas , Hepatócitos/metabolismo , Humanos , Indazóis/análise , Indazóis/metabolismo , Indazóis/farmacocinética , Masculino , Piridinas/análise , Piridinas/metabolismo , Piridinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas por Ionização por Electrospray/métodos
7.
Planta Med ; 86(2): 144-150, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31766069

RESUMO

A UHPLC-photodiode array-MS method was developed and validated for the quantification of one chromone and six anthraquinone type of compounds from Bulbine natalensis plant samples and dietary supplements. Metabolites 1:  -  7: were identified based on their retention times and electrospray ionization-MS spectra compared with a mix of previously isolated compounds. The quantification of 1:  -  7: was based on photodiode array detection. The optimized separation was achieved using a CORTECS C18 column with a gradient of water/acetonitrile as the mobile phase. Seven compounds were separated within 15 minutes with detection limits of 50 pg on the column. The analytical method was validated for linearity, repeatability, accuracy, limits of detection, and limits of quantification. The relative standard deviations for intra- and inter-day experiments were less than 5% and the recovery efficiency was 98 - 101%. Nine dietary supplements labeled as containing B. natalensis were examined. Anthraquinone-type compounds were detected in only five out of nine dietary supplements, with the total amount ranging from 11.3 to 90.4 mg per daily dose. The analytical method is simple, economic, rapid, and can be applied for quality assessment of B. natalensis and dietary supplements. Electrospray ionization-MS was used for the identification of these compounds in plant samples and dietary products.


Assuntos
Antraquinonas/análise , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Xanthorrhoeaceae/química , Limite de Detecção , Estrutura Molecular
8.
Food Chem Toxicol ; 135: 110882, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31622727

RESUMO

Round scad (Decapterus maruadsi) was hydrolyzed with a double-enzyme (a mixture of neutrase and trypsin) to obtain antioxidant peptides. The round scad hydrolysates obtained by 5-h hydrolysis (RSH) displayed the strongest antioxidant activities, which could scavenge the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, the hydroxyl radical, and exhibit reducing power. RSH was further separated into four fractions by using an ultrafiltration membrane system, and low-molecular-weight fraction RSH-IV (<5 kDa) showed the highest antioxidant activities. Fraction RSH-IV was then purified with gel filtration chromatography followed by reverse high-performance liquid chromatography (RP-HPLC). The sequence of the purified antioxidant peptide was identified as Lys-Gly-Phe-Arg (506 Da) by liquid chromatography/electrospray ionization tandem mass spectrometry (LC-MS/MS). Additionally, the purified peptide could scavenge DPPH radical at IC50 value of 0.13 mg/mL, and it showed a 49.08-fold higher DPPH radical scavenging activity compared with that of the crude RSH. The results suggest that antioxidant peptides obtained from round scad (Decapterus maruadsi) could be a good source of natural antioxidant.


Assuntos
Antioxidantes/metabolismo , Cromatografia Líquida/métodos , Proteínas de Peixes/metabolismo , Peixes/metabolismo , Peptídeos/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Hidrólise
9.
J Chromatogr A ; 1609: 460432, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31431355

RESUMO

Microcystins (MCs) are cyclic heptapeptide toxins produced by various cyanobacterial genera that are toxic to both animals and humans. In this study, a novel strategy was proposed for the quantitation of nine MCs and Nodularin-R (NOD) in lake water using UHPLC-MS/MS under negative ionization mode, in which only centrifugation was employed during sample preparation. As a result, limits of quantification (LOQ) ranging from 0.05 to 0.1 µg/L for all studied compounds were obtained in water samples, which were lower than the results obtained using positive ionization mode. Additionally, validation was performed by spiking three different levels of MCs at 0.05 or 0.1, 0.5, 1.0 µg/L (n = 6). Recoveries ranged from 88.6% to 101.8%, and intraday and interday variability were lower than 12% and 14%, respectively, for all targeted compounds. Furthermore, the proposed method was applied to investigate microcystins contamination in fifty lake water samples collected in different regions in China. As a result, MC-LR, MC-RR, MC-YR, MC-WR, MC-LW, MC-LA, MC-LY, and MC-HilR were detected in lake water samples at trace level ranging from 0.06 to 0.37 µg/L. The obtained results indicated that it was necessary to monitor the presence of MCs in lake water, especially during regular cyanobacterial blooms during warmer months.


Assuntos
Cromatografia Líquida/métodos , Lagos/química , Microcistinas/análise , Peptídeos Cíclicos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise , Animais , China , Limite de Detecção
10.
Biomed Chromatogr ; 34(1): e4697, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31495945

RESUMO

A liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) method was developed and validated to measure GDC-0084 in human plasma and cerebrospinal fluid (CSF). Reverse-phase chromatography with gradient elution was performed using a C18 column (50 × 2.0 mm, 3 µm). Solid-phase extraction of plasma and CSF was employed to give excellent recovery. MS detection was performed with positive ion screening in multiple reaction monitoring mode. The precursor to the product ions (Q1 → Q3) selected for GDC-0084 and GDC-0084-d6 were 383.2 → 353.2 and 389.2 → 353.2, respectively. A separate calibration curve was established for human plasma and CSF. Both calibration curves, ranging from 0.2 to 200 ng/mL, were linear and had acceptable intra- and inter-day precision and accuracy. The lower limit of quantitation and limit of detection for GDC-0084 in human plasma were 0.2 ng/mL (signal/noise ≥47) and 0.005 ng/mL (signal/noise ≥3.5), respectively, and for GDC-0084 in human CSF were 0.2 ng/mL (signal/noise ≥19.7) and 0.04 ng/mL (signal/noise ≥7.2). This method was successfully applied to analyze serial plasma samples obtained from children with diffuse intrinsic pontine gliomas and other midline gliomas who participated in pharmacokinetic studies as part of a phase I clinical trial of GDC-0084.


Assuntos
Cromatografia Líquida/métodos , Oxazinas/sangue , Oxazinas/líquido cefalorraquidiano , Pirimidinas/sangue , Pirimidinas/líquido cefalorraquidiano , Espectrometria de Massas em Tandem/métodos , Criança , Estabilidade de Medicamentos , Humanos , Limite de Detecção , Modelos Lineares , Oxazinas/química , Oxazinas/farmacocinética , Pirimidinas/química , Pirimidinas/farmacocinética , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos
11.
J Mass Spectrom ; 55(1): e4470, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31756784

RESUMO

The first 17 amino acid residues of Huntingtin protein (Nt17 of htt) are thought to play an important role in the protein's function; Nt17 is one of two membrane binding domains in htt. In this study the binding ability of Nt17 peptide with vesicles comprised of two subclasses of phospholipids is studied using electrospray ionization - mass spectrometry (ESI-MS) and molecular dynamics (MD) simulations. Overall, the peptide is shown to have a greater propensity to interact with vesicles of phosphatidylcholine (PC) rather than phosphatidylethanolamine (PE) lipids. Mass spectra show an increase in lipid-bound peptide adducts where the ordering of the number of such specie is 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) > 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine (POPC) > 1-palmitoyl-2-oleoyl-sn-glycero-3 phosphoethanolamine (POPE). MD simulations suggest that the compactness of the bilayer plays a role in governing peptide interactions. The peptide shows greater disruption of the DOPC bilayer order at the surface and interacts with the hydrophobic tails of lipid molecules via hydrophobic residues. Conversely, the POPE vesicle remains ordered and lipids display transient interactions with the peptide through the formation of hydrogen bonds with hydrophilic residues. The POPC system displays intermediate behavior with regard to the degree of peptide-membrane interaction. Finally, the simulations suggest a helix stabilizing effect resulting from the interactions between hydrophobic residues and the lipid tails of the DOPC bilayer.


Assuntos
Proteína Huntingtina/química , Simulação de Dinâmica Molecular , Peptídeos/química , Fosfolipídeos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Aminoácidos/química , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligação Proteica , Relação Estrutura-Atividade
12.
Biomed Chromatogr ; 34(2): e4759, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31758604

RESUMO

Temocillin is a ß-lactamase-resistant penicillin used for the treatment of multiple drug-resistant Gram-negative bacteria. To maximize efficacy and avoid adverse effects, the dose regimen has to be quickly adjusted to the clinical situations. This necessitates the development of a rapid, reliable and accurate analytical method. Temocillin and the stable isotopically labeled internal standard ([13 C6 ]-amoxicillin) were extracted from either serum or cerebrospinal fluid by a turbulent flow liquid chromatographic method and eluted onto an octadecyl-silica phase with polar endcapping. Mass spectrometry was conducted using an exact mass determination method by electrospray positive ionization high-resolution mass spectrometry. The LLOQ and ULOQ of the present method were determined to be 0.4 and 200 µg/ml for serum and cerebrospinal fluid samples, respectively. The total analysis time was <7 min. The recovery ranged from 87.7 to 120.8%. Intra- and inter-day precision and trueness were tested at four concentration levels: 0.4, 8, 40 and 160 µg/ml. Values were 6.33 ± 1.53, 8.8 ± 1.3, 8.8 ± 0.36 and 2.1 ± 0.76%, and 5.0 ± 0.54, 9.9 ± 1.0, 5.8 ± 1.6 and 0.1 ± 1.1%, for inter- and intra-day analysis, respectively. Temocillin was found to be stable under all relevant laboratory conditions. The method was cross-validated with a microbiological assay. This method is suitable for accurate measurement of temocillin concentration in small volumes of serum or cerebrospinal fluid. Thanks to the online extraction procedure, the overall analytical time is compatible with high-throughput analysis for clinical application.


Assuntos
Cromatografia Líquida/métodos , Penicilinas/sangue , Penicilinas/líquido cefalorraquidiano , Espectrometria de Massas por Ionização por Electrospray/métodos , Antibacterianos/sangue , Antibacterianos/líquido cefalorraquidiano , Antibacterianos/farmacologia , Humanos , Limite de Detecção , Modelos Lineares , Testes de Sensibilidade Microbiana , Penicilinas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Reprodutibilidade dos Testes
13.
J Mass Spectrom ; 55(1): e4484, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31786817

RESUMO

Qixianqingming granules (QXQM) comprise a traditional Chinese medicine (TCM) formula that was developed based on the combination of TCM theory and clinical practice. This formula has been proven to effectively treat asthma. In this study, an analytical procedure using ultraperformance liquid chromatography, coupled with electrospray ionization quadrupole time-of-flight mass spectrometry, was established for the rapid separation and sensitive identification of the chemical components in QXQM and its metabolites in serum of rats. Seventy-two compounds were systematically identified in QXQM, including flavonoids, terpenoids, anthraquinones, phenylethanoid glycosides, stilbenes, alkaloids, and organic acids. Thirteen prototype compounds and 29 metabolites were detected in the serum of rats. The results provided fundamental information for further studying the mechanisms and clinical application of QXQM.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Alcaloides/análise , Alcaloides/metabolismo , Animais , Antraquinonas/análise , Antraquinonas/metabolismo , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/metabolismo , Flavonoides/análise , Flavonoides/metabolismo , Glicosídeos/análise , Glicosídeos/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Estilbenos/análise , Estilbenos/metabolismo , Terpenos/análise , Terpenos/metabolismo
14.
J Agric Food Chem ; 68(1): 418-425, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31829625

RESUMO

For quick, noninvasive, and high-sensitivity surface analysis of foods and agricultural products, a touch sensor was developed and applied to sheath-flow probe electrospray ionization/mass spectrometry (sfPESI/MS). Upon making contact with the sample, the probe stopped by detecting the current flowing through the circuit and analytes on the sample surface were extracted in the solvent preloaded in the plastic capillary. By lifting up the probe to the default position, an electrospray ionization mass spectrum of the sample was obtained. By scanning the sample stage using a programming tool, a point analysis of targeted positions of biological samples with a spot diameter of ≤0.3 mm was achieved. It took less than 10 s for one sample spot. This method was applied to various plants and animal tissues.


Assuntos
Análise de Alimentos/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Galinhas , Decapodiformes/química , Peixes , Análise de Alimentos/instrumentação , Frutas/química , Carne/análise , Plantas/química , Espectrometria de Massas por Ionização por Electrospray/instrumentação
15.
J Dairy Sci ; 103(1): 72-86, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677836

RESUMO

The aim of this study was to characterize minor lipids in methanol fraction extracted from raw camel milk after loading it on a water-preconditioned short C18 open column and fractionating with a gradient of methanol/water. The C18 column showed high fractionation efficiency of minor lipids, such as glycosphingolipids, lipopolysaccharides, or oligosaccharides, when compared with other constituents, in particular polysaccharides, proteins, and free fatty acids. Liquid chromatography electrospray ionization tandem mass spectrometry in negative ion mode was used to identify 21 new glycosphingolipids, lipopolysaccharides, and oligosaccharides. Electrospray ionization tandem mass spectrometry was qualified to provide relevant data for recognizing the molecular mass, glycosylation sequences, and structure of saccharide moieties for the revealed compounds. The sequence of combinations of one selected lipopolysaccharide, which was considered the backbone of the remaining lipopolysaccharides, was confirmed in a density functional theory study. The obtained results showed that the tested fraction is a rich source of glycosphingolipids, lipopolysaccharides, and oligosaccharides with antioxidant activity.


Assuntos
Camelus , Lipídeos/farmacologia , Leite/química , Oligossacarídeos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espectrometria de Massas por Ionização por Electrospray/veterinária , Animais , Humanos , Lipídeos/química , Oligossacarídeos/química , Plasma , Espectrometria de Massas por Ionização por Electrospray/métodos
16.
Talanta ; 206: 120236, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514837

RESUMO

This work presents a reliable analytical procedure combining micro-extraction by packed sorbent (MEPS) and ultra-high performance liquid chromatography-electrospray ionization tandem mass spectrometry to determine 8-iso prostaglandin F2α, 8-iso prostaglandin E2 and prostaglandin E2 in dried blood spots (DBSs). To reach this goal, we optimized a fast semi-automated MEPS procedure for the clean-up and pre-concentration of the analytes extracted from a single DBS (50 µL) by a 70:30 v/v methanol:water mixture. Limits of detection of about 20 pg mL-1, satisfactory recoveries (90-110%) and very good intra- and inter-day precisions (RSD ≤10%) were obtained for all the analytes. The innovative addition of internal standards on the filter paper before DBS sampling allowed to compensate changes in the amount of analyte during storage. Since prostanoids and isoprostanoids are biomarkers involved in the pathogenesis and progression of many diseases (e.g. ductal patency, diabetic nephropathy, and acute lung injury), our analytical method offers interesting diagnostic and prognostic opportunities in the medical field. The present method is currently used for the analysis of such biomarkers in DBSs from preterm newborns collected in the clinical setting.


Assuntos
Dinoprosta/análogos & derivados , Dinoprostona/análogos & derivados , Dinoprostona/sangue , Teste em Amostras de Sangue Seco/métodos , Isoprostanos/sangue , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão/métodos , Dinoprosta/sangue , Humanos , Recém-Nascido , Limite de Detecção , Microextração em Fase Sólida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
17.
J Pharm Biomed Anal ; 177: 112844, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491659

RESUMO

Traditionally, for a liquid chromatography tandem mass spectrometry (LC-MS/MS) bioanalytical assay, an external calibration curve is required to achieve accurate quantitation of an analyte. Recently, a novel in-sample calibration curves (ISCC) methodology that can achieve quick and accurate LC-MS/MS bioanalysis without the use of an external calibration curve was reported. The ISCC methodology utilizes the presence of multiple naturally occurring isotopologues of a stable isotopically labeled analyte to construct an in-sample calibration curve for the quantification. This methodology has great potential in many applications, for example biomarker measurement, quantitative proteomics and clinical diagnosis. Here, we assessed the feasibility of applying this ISCC-LC-MS/MS methodology in regulated bioanalysis using BMS-984478, a drug candidate, as the model compound. We also proposed method validation procedures/processes for this new approach for industry peers' consideration and feedback. A LC-MS/MS method using the ISCC strategy was successfully developed and validated for the quantitative analysis of BMS-984478 in human plasma over the range of 1.33-993.42 ng/mL. The validated ISCC-LC-MS/MS method was compared with a previously validated method using the conventional external calibration curve approach, and the two methods showed equivalent performance. Critical considerations and practical approaches in method development, validation and sample analysis were also discussed. Our work demonstrated that the ISCC-LC-MS/MS methodology is a promising approach for regulated LC-MS/MS bioanalysis. ISCC-LC-MS/MS methodology has its unique advantages and has great potential to be widely applied for various quantitative applications, and may even change the landscape of quantitative analysis.


Assuntos
Antivirais/isolamento & purificação , Fracionamento Químico/métodos , Espectrometria de Massas em Tandem/métodos , Antivirais/administração & dosagem , Antivirais/sangue , Calibragem , Cromatografia Líquida/métodos , Estudos de Viabilidade , Humanos , Limite de Detecção , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização por Electrospray/normas , Espectrometria de Massas em Tandem/normas
18.
J Pharm Biomed Anal ; 177: 112835, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31499428

RESUMO

Tuberculosis of cervical lymph nodes is called scrofula in Traditional Chinese Medicine (TCM). Clinical manifestation is that unilateral or bilateral neck can have multiple enlarged lymph nodes of different sizes. Current therapeutic drugs include Lysionotus pauciflorus Maxim. tablets and compound of Lysionotus pauciflorus Maxim., which have a significant effect on tuberculosis of cervical lymph nodes. This compound is composed of three herbs, Lysionotus pauciflorus Maxim., Prunella vulgaris L. and Artemisia argyi Levl.et Vant. A selective and sensitive LC-MS/MS method was established and validated in rat plasma for the first time. Chromatographic separation was achieved on a Wonda Cract ODS-2 C18 Column (150 mm × 4.6 mm, 5 µm). The mobile phase contained 0.1% formic acid aqueous solution and acetonitrile with a flow rate of 0.8 mL/min. The detection was performed in negative electrospray ionization mode and the precursor/product ion transitions of six components and internal standard (IS) sulfamethoxazole were quantified in multiple reaction monitoring (MRM) using QTRAP-3200 MS/MS. The method fulfilled US Food and Drug Administration guidelines for selectivity, sensitivity, accuracy, precision, matrix effect, extraction recovery, dilution integrity, and stability. This proposed method was then successfully applied to a pharmacokinetic study after oral administration of 10 mL/kg compound extracts in rats. The pharmacokinetic parameters and plasma concentration-time profiles would prove valuable in pre-clinical and clinical investigations on the disposition of compound medicine.


Assuntos
Medicamentos de Ervas Chinesas/análise , Lamiales/química , Espectrometria de Massas em Tandem/métodos , Administração Oral , Animais , Ácidos Cafeicos/administração & dosagem , Ácidos Cafeicos/sangue , Ácidos Cafeicos/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacocinética , Flavonas/administração & dosagem , Flavonas/sangue , Flavonas/farmacocinética , Glucosídeos/administração & dosagem , Glucosídeos/sangue , Glucosídeos/farmacocinética , Masculino , Modelos Animais , Fenilpropionatos/administração & dosagem , Fenilpropionatos/sangue , Fenilpropionatos/farmacocinética , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos , Comprimidos , Tuberculose dos Linfonodos/tratamento farmacológico
19.
J Pharm Biomed Anal ; 177: 112839, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31505430

RESUMO

Parenteral amino acid solutions containing tryptophan tend to develop a yellow colouration upon storage. Hence, the aim of the present study was to find out whether tryptophan degradation products are the reason for the yellowing. The degree of discolouration and tryptophan degradation was examined by visual examination and UV/Vis measurements with respect to oxygen presence, pH value, and duration of steam sterilization. LC-UV analyses of autoclaved tryptophan solutions indicated eight degradation products, namely R,R/R,S 2-amino-3-(oxoindolin-3-yl)propanoic acid, R,R/R,S 2-amino-3-hydroxy-2-oxoindolin-3-yl)propanoic acids, cis/trans 3a-hydroxy-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole-2-carboxylic acid, N´-formylkynurenine, and kynurenine. The proposed degradation products were confirmed by spiking of synthesized degradation products and LC-UV/MS analyses. The LC-UV analysis method was optimized and validated according to the ICH guideline Q2 (R1). Tryptophan stability in commercially available parenteral amino acid formulations was evaluated over a storing period of 12 months in two common types of primary packaging after autoclave procedure.


Assuntos
Cor , Soluções de Nutrição Parenteral/química , Controle de Qualidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Triptofano/química , Cromatografia Líquida de Alta Pressão/métodos , Embalagem de Medicamentos/métodos , Embalagem de Medicamentos/normas , Estabilidade de Medicamentos , Armazenamento de Medicamentos/normas , Oxirredução , Soluções de Nutrição Parenteral/normas
20.
J Pharm Biomed Anal ; 177: 112843, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31509788

RESUMO

An UHPLC method was developed for the determination of 15 prenylflavonoids from aerial parts of Epimedium grandiflorum and related species (Berberidaceae). The separation was achieved using a reverse phased column and water/acetonitrile gradient as a mobile phase at a temperature of 40°C. The developed analytical method was validated for linearity, limits of detection (LOD) and limits of quantification (LOQ), stability and repeatability. The LOD and LOQ were found to be in the range from 0.1-0.5 µg/mL and 0.3-1 µg/mL, respectively. The wavelength used for quantification with the photodiode array detector was 269 nm. The total content of 15 prenylflavonoids was 9.1-20.6 mg/g for E. grandiflorum (except for sample #2899 and #20862), 5.6-35.4 mg/g for E. brevicornu and 10.8-30.5 mg/g for E. sagittatum. Twenty dietary supplements contained in the range from 0.1 to 81.7 mg/day. The developed method is simple, rapid and especially suitable for quality assessment of E. grandiflorum and dietary supplements containing E. grandiflorum. Liquid chromatography quadrupole time-of-flight-mass spectrometry (LC-QToF) is described for the identification and confirmation of compounds in plant samples and dietary supplements. This technique is also used for chemical profiling of Epimedium samples. This method involved the use of protonated ions in the positive ion mode and deprotonated ions in the negative ion mode with extracted ion chromatogram (EIC). Chemometric analytical tools for visualizing the plant and commercial samples quality were used for discriminating between Epimedium species and dietary supplements with regards to the relative content or presence of components. A HPTLC method was also developed for the fast chemical fingerprint analysis of Epimedium species.


Assuntos
Suplementos Nutricionais/análise , Epimedium/química , Flavonoides/análise , Controle de Qualidade , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/normas , Estudos de Viabilidade , Flavonoides/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Componentes Aéreos da Planta/química , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos
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