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1.
Fa Yi Xue Za Zhi ; 38(4): 473-477, 2022 Aug 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-36426690

RESUMEN

OBJECTIVES: To establish a method to identify unknown sample based on the combined use of Fourier transform infrared spectroscopy (FTIR), gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry (UPLC-LTQ-Orbitrap MS) and 1H-nuclear magnetic resonance spectroscopy (1H-NMR) technique. METHODS: The unknown sample was directly analyzed by FTIR. The unknown sample was dissolved in methanol solution containing internal standard SKF525A and the supernatant was detected by GC-QTOF-MS and UPLC-LTQ-Orbitrap MS. The unknown sample was dissolved in methanol-d4 solution for structural analysis of 1H-NMR. RESULTS: The characteristic absorption peaks of FTIR spectra obtained from unknown sample were 1 682 (C=O bond), 1 503, 1 488, 1 436, 1 363, 1 256, 1 092, 1 035, 935, 840 and 800 cm-1, the characteristic fragment ions (m/z) of GC-QTOF-MS were 86.096 4 (base peak), 58.065 1, 149.023 5, 121.028 6 and 65.038 6, the accurate mass [M+H]+ detected by UPLC-LTQ-Orbitrap MS was 236.127 7. The sample was identified as synthetic cathinone new psychoactive substance Eutylone by 1H-NMR. CONCLUSIONS: The method established in this study can be used for structural confirmation of Eutylone.


Asunto(s)
Metanol , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectroscopía de Resonancia Magnética
2.
Fa Yi Xue Za Zhi ; 37(4): 511-515, 2021 Aug.
Artículo en Zh | MEDLINE | ID: mdl-34726004

RESUMEN

ABSTRACT: Objective To detect the uncontrolled new psychoactive tryptamines involved in drug-related cases with high resolution mass spectrometry and nuclear magnetic resonance spectroscopy. Methods White and brown powder obtained in actual cases were extracted and analyzed by gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry (UPLC-LTQ-Orbitrap MS) and 1H-nuclear magnetic resonance spectroscopy (1H-NMR). Results After detection by GC-QTOF-MS, the components of white powder showed main characteristic fragment ion peaks at m/z 218.141 0 (molecular ion peak), 72.080 6 (base peak), etc. After detection by UPLC-LTQ-Orbitrap MS, its protonated molecular ion was m/z 219.149 4. The main ions in the secondary mass spectrum under the collision-induced dissociation (CID) mode were m/z 160.076 3 and 72.080 8. After detection by GC-QTOF-MS, the components of brown powder showed main characteristic fragment ion peaks at m/z 246.135 7 (molecular ion peak), 58.065 1 (base peak), etc. After detection by UPLC-LTQ-Orbitrap MS, its protonated molecular ion was m/z 247.145 0. The main ions in the secondary mass spectrum under CID mode were m/z 202.087 1, 160.076 3 and 134.060 5. NIST 17 library retrieval and 1H-NMR confirmed that the white powder and brown powder contained new psychoactive tryptamines 4-OH-MET and 4-AcO-DMT, respectively. Conclusion GC-QTOF-MS, UPLC-LTQ-Orbitrap MS and 1H-NMR can be used together to identify unknown new psychoactive substances.


Asunto(s)
Triptaminas , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Espectrometría de Masas
3.
Phytochem Anal ; 31(3): 395-407, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31908080

RESUMEN

INTRODUCTION: Hederacoside C (HDC) is a bioactive natural triterpenoid saponins constituent originating from traditional Chinese medicines, playing an important role in the treatment of acute respiratory infections and chronic inflammatory bronchitis. Meanwhile, it is recognised by Korea as a botanical drug. OBJECTIVES: In order to develop an integrated template approach to analysing screening and identification of the metabolites of traditional Chinese medicines. This study will provide available information for further pharmaceutical studies of HDC and other triterpene saponins. METHODOLOGY: An analysis strategy based on ultrahigh-performance liquid chromatography quadrupole Orbitrap mass spectrometry (UHPLC-Q-Orbitrap-MS) technique combined with automatic fragment ion search (FISh) was firstly exploited for the characterisation metabolites of HDC in vivo and in vitro. Accurate full mass scan combined with an on-line FISh annotations approach was developed to rapidly identify all the potential metabolites of HDC. Furthermore, FISh accurately located the structure of the target compound in a large number of mass spectral data. RESULTS: A total of 34 metabolites were detected and tentatively identified by analysing comprehensive biological samples. The results clearly demonstrated that HDC underwent general metabolic reactions including dealkylation, reduction, oxidation, desaturation, dehydration, cysteine conjugation, GSH conjugation, taurine conjugation, and glycine conjugation to produce 26 phase I and eight phase II metabolites. CONCLUSION: In the present study, UHPLC-Q-Exactive Orbitrap MS technique combined with FISh provided a rapid and efficient platform to characterise metabolites of HDC in vivo and in vitro. The proposed method could develop an integrated template approach to screen and identify the constituents and metabolites of traditional Chinese medicines.


Asunto(s)
Ácido Oleanólico , Animales , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Espectrometría de Masas , Ácido Oleanólico/análogos & derivados
4.
BMC Genomics ; 19(1): 719, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30285610

RESUMEN

BACKGROUND: High-throughput proteomics was used to determine the role of the fish liver in defense responses to bacterial infection. This was done using a rainbow trout (Oncorhynchus mykiss) model following infection with Aeromonas salmonicida, the causative agent of furunculosis. The vertebrate liver has multifaceted functions in innate immunity, metabolism, and growth; we hypothesize this tissue serves a dual role in supporting host defense in parallel to metabolic adjustments that promote effective immune function. While past studies have reported mRNA responses to A. salmonicida in salmonids, the impact of bacterial infection on the liver proteome remains uncharacterized in fish. RESULTS: Rainbow trout were injected with A. salmonicida or PBS (control) and liver extracted 48 h later for analysis on a hybrid quadrupole-Orbitrap mass spectrometer. A label-free method was used for protein abundance profiling, which revealed a strong innate immune response along with evidence to support parallel rewiring of metabolic and growth systems. 3076 proteins were initially identified against all proteins (n = 71,293 RefSeq proteins) annotated in a single high-quality rainbow trout reference genome, of which 2433 were maintained for analysis post-quality filtering. Among the 2433 proteins, 109 showed significant differential abundance following A. salmonicida challenge, including many upregulated complement system and acute phase response proteins, in addition to molecules with putative functions that may support metabolic re-adjustments. We also identified novel expansions in the complement system due to gene and whole genome duplication events in salmonid evolutionary history, including eight C3 proteins showing differential changes in abundance. CONCLUSIONS: This study provides the first high-throughput proteomic examination of the fish liver in response to bacterial challenge, revealing novel markers for the host defense response, and evidence of metabolic remodeling in conjunction with activation of innate immunity.


Asunto(s)
Aeromonas salmonicida/fisiología , Proteínas de Peces/metabolismo , Hígado/metabolismo , Hígado/microbiología , Oncorhynchus mykiss/metabolismo , Oncorhynchus mykiss/microbiología , Proteómica , Animales , Ontología de Genes , Hígado/inmunología , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/inmunología , Mapeo de Interacción de Proteínas
5.
J Sep Sci ; 37(7): 782-91, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24478185

RESUMEN

A new method combining the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method with ultra high performance liquid chromatography and ESI quadrupole Orbitrap high-resolution MS was developed for the highly accurate and sensitive screening of 69 dyes in wines. Response surface methodology was employed to optimize the QuEChERS sample preparation method for the determination of 69 different analytes in wines for the first time. After optimization, the maximum predicted recovery was 99.48% rate for canacert indigo carmine under the optimized conditions of 10 mL acetonitrile, 1.45 g sodium acetate, 107 mg primary secondary amine, and 96 mg C18 . For the matrices studied, the recovery rates of the other 68 compounds ranged from 87.2-107.4%, with coefficient of variation < 6.4%. The mass accuracy typically obtained is routinely better than 1.6 ppm and only needed to be calibrated once a week. The LODs for the analytes are in the range 1-1000 µg/kg. This method has been successfully applied on screening of dyes in commercial wines, and it is very useful for the fast screening of different food additives.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Colorantes/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Vino/análisis
6.
Se Pu ; 41(11): 986-994, 2023 Nov.
Artículo en Zh | MEDLINE | ID: mdl-37968817

RESUMEN

Mycotoxins have carcinogenic, mutagenic, hepatotoxic, nephrotoxic, immunotoxic, neurotoxic, and teratogenic properties. Thus, these substances have attracted significant attention because they pose a threat to human health. As research on mycotoxins deepens, new structural analogues of mycotoxins are constantly being discovered. In this study, a method based on high performance liquid chromatography-quadrupole/orbitrap mass spectrometry was established for the simultaneous determination of 22 mycotoxins in milk. A simple, effective, and rapid pretreatment method was optimized by focusing on the solvent type, extractant volume, and extracting salt based on the characteristics of the mycotoxins and sample matrix. The analytes were extracted using 0.5% formic acid acetonitrile solution and added with sodium chloride to separate fats from water. The samples were centrifuged at 8000 r/min (4 ℃) for 5 min using a centrifuge and then concentrated using nitrogen. The dry residue was dissolved with 50% methanol aqueous solution. Twenty-two mycotoxins were separated on a ZORBAX Eclipse Plus C18 chromatographic column (100 mm×2.1 mm, 1.7 µm), and quantitative analysis was performed using the isotope internal standard method. The analytes were determined by liquid chromatography-quadrupole/orbitrap mass spectrometry in positive electrospray ionization mode. Qualitative analyses of the compounds were performed in full mass spectrometry/data-dependent tandem mass spectrometry (MS/dd-MS2) mode. Good linearities in the range of 0.5-100.0 µg/L were observed for the 22 mycotoxins, and the correlation coefficients (R2) were greater than 0.999. The limits of detection (S/N=3) and quantification (S/N=10) ranged from 0.3 to 0.5 µg/kg and from 1.0 to 1.5 µg/kg, respectively. The average recoveries of the 22 mycotoxins at three spiked levels of 1.5, 5.0, and 15 µg/kg were between 84.7% and 100.8%, with relative standard deviations (RSDs) of 1.2%-9.9%. These findings indicate that the method has high sensitivity and accuracy as well as good precision. Finally, the method was applied to the detection and analysis of mycotoxins in 25 actual commercial milk samples. The results revealed that the selected samples were not contaminated with any of the mycotoxins analyzed. Thus, the proposed method is useful as a quick preprocessing and confirmatory method for the simultaneous determination of mycotoxins in milk.


Asunto(s)
Micotoxinas , Humanos , Animales , Micotoxinas/análisis , Leche/química , Cromatografía Liquida , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión
7.
Food Chem X ; 18: 100705, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37397214

RESUMEN

The complex oligosaccharides (OS) in different milk are more difficult to detect and complicated to analyze as their enormous structural complexity. UPLC-QE-HF-MS was supposed to be a highly effective method for OS identification. In present study, 70 human milk oligosaccharides (HMOs), 14 bovine milk oligosaccharides (BMOs), 23 goat milk oligosaccharides (GMOs) and 24 rat milk oligosaccharides (RMOs) were detected by using UPLC-QE-HF-MS, respectively. There were highly differences in number and composition between the four milk OS. 14 neutral and 3 acidic OS were firstly found in rat milk. The composition and abundances of RMOs were might more similar to that of HMOs, comparing with BMOs and GMOs. The similarity between HMOs and RMOs might provide theoretical basis for better application of rats in biological/biomedical studies of HMOs as models. The BMOs and GMOs were expected to be suitable for applications in medical and functional foods as a promising bioactive molecular.

8.
Food Chem X ; 17: 100557, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36845481

RESUMEN

The current research was characterized on phenolic metabolite profile including six chemical structures (phenolic acid, luteolin, orientin, apigenin, isoscoparin, and tricin) in wheat seedlings using HPLC-Q-Orbitrap-MS/MS and NMR techniques. Our study was also was the first to demonstrate fluctuations of isolated nine phenolic contents and antioxidant properties in various cultivars of this species with different growth times. The antioxidant abilities differed significantly in the 80 % methanol extracts (600 µg/mL) according to cultivar and growth time, with the highest average activities (DPPH: 82 %; ABTS: 87 %) observed after 7 days. The isolated nine compositions exhibited considerable differences in cultivars and growth times, specifically, isoorientin (6) and isochaftoside (8) were observed the most abundant average contents (99.3; 64.3 mg/100 g), representing approximately 28.3 and 18.3 % (total content: 350.8 mg/100 g). Their total phenolics showed the highest rates (420.8 mg/100 g) at 7 days, followed by 9 â†’ 5 â†’ 12 â†’ 14 days with 374.6 â†’ 366.7 â†’ 350.7 â†’ 241.1 mg/100 g, as the rank orders of antioxidant effects. These findings suggest that wheat seedlings may be a potent source of functional agents.

9.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1201-1202: 123278, 2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35561641

RESUMEN

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is the leading cause of morbidity and mortality in COPD management. However, detecting the progression from the stable stage to acute exacerbation mainly depends on doctors' judgment of clinical symptoms, and there is no biomarker that can be used for auxiliary clinical diagnosis. In this work, serum samples from COPD patients (n = 82) and healthy subjects (n = 29) were collected and analyzed. Patients with COPD were divided into stable COPD (SCOPD) and AECOPD groups, with the latter comprising subtypes 1 and 2. High-coverage lipidomics profiling of 913 lipids belonging to 19 subclasses was carried out by liquid chromatography-Q-Exactive orbitrap mass spectrometry. We performed 4 cross-comparisons to characterize metabolic disturbances associated with the progression of stable COPD to AECOPD-ie, SCOPD vs healthy subjects, AECOPD vs SCOPD, AECOPD subtype 1 vs SCOPD, and AECOPD subtype 2 vs SCOPD. We tentatively identified 86 lipids with differential abundance among groups, lipids that were altered from the stable stage of disease to AECOPD included sphingolipids, ether-containing glycerophospholipids, phosphatidylglycerols, and glycerol lipids. Three panels of lipid biomarkers specific to AECOPD, AECOPD subtypes 1 and 2 vs SCOPD yielded areas under the receiver operating characteristic curve of 0.788, 0.921 and 0.920, respectively, with sensitivity of 77.5%, 80.7% and 91.3%, respectively, and specificity of 75.8%, 97.0% and 87.9%, respectively. The result indicated differences in lipid metabolism may underlie AECOPD and its 2 subtypes and can serve as biomarkers for early diagnosis, and high-coverage lipidomics proved to be an accurate approach to profile the lipid metabolism in biological samples.


Asunto(s)
Lipidómica , Enfermedad Pulmonar Obstructiva Crónica , Enfermedad Aguda , Biomarcadores , Humanos , Lípidos
10.
J Chromatogr A ; 1678: 463366, 2022 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-35914410

RESUMEN

Sexual enhancement dietary supplements have often been adulterated with phosphodiesterase type 5 (PDE-5) inhibitors used for treatment of erectile dysfunction, and widely distributed through online markets. As the illegal adulterants, the original PDE-5 inhibitor drugs and a numerous number of synthetized analogues, more than 80, have already been found. Therefore, analytical methods that detect various PDE-5 inhibitors and uncover newly synthesized analogues are needed. In this study, we have developed a rapid and reliable screening method for PDE-5 inhibitors and their structural analogues by using liquid chromatography-tandem mass spectrometry (LC-MS/MS) followed by hierarchical clustering based on similarity of MS/MS spectra. Forty reference standards of PDE-5 inhibitors/analogues were measured using a quadrupole-orbitrap mass spectrometer in data-dependent mode. The 60 most intense fragment ions were extracted from each MS/MS spectra, and the ions observed within 1.5 mDa mass tolerance were considered to be the same ion. Based on fragment ion tables representing detected ions for each compound, hierarchical clustering was performed. The resulting dendrogram showed that the reference standards were separated into seven clusters according to their characteristic structures. Subsequently, two additional standards spiked into a herbal sample were analyzed. While herbal components were clearly separated from the clusters of the reference standards, the spiked standards were clustered closely with the structurally similar standards. Furthermore, application of our method to dietary supplements allowed for detection of sildenafil and tadalafil as adulterants. These results suggest that our screening method facilitates discovery of adulterant PDE-5 inhibitors/analogues by illustrating their structural similarity.


Asunto(s)
Inhibidores de Fosfodiesterasa 5 , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida , Análisis por Conglomerados , Suplementos Dietéticos/análisis , Contaminación de Medicamentos , Iones , Inhibidores de Fosfodiesterasa 5/análisis , Citrato de Sildenafil , Espectrometría de Masas en Tándem/métodos
11.
Food Chem X ; 16: 100470, 2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36313273

RESUMEN

The fruit peel of a color mutant jujube cultivar, 'Sanbianhong' (SBF), was investigated using an ultra-high performance liquid chromatography quadrupole Orbitrap mass spectrometry (UHPLC-Q-Orbitrap MS) at five ripening stages (S1, Young fruit stage; S2, swelling stage; S3, white-mature stage; S4, pre-mature stage and S5, mature stage). Lutein, ß-carotene, chlorophyll a, chlorophyll b, and 13 anthocyanins were identified. Chlorophyll a and cyanidin 3-O-galactoside were considered key color metabolites in S1 with the content of 1.083 mg/g of fresh weight (FW) and 4.585 mg/g of FW, respectively. Delphinidin (0.488 mg/g FW) and cyanidin (6.259 mg/g FW) were identified as the key pigments in S3. Delphinidin 3-O-glucoside (0.256 mg/g FW) was identified as the key anthocyanin in maturity S5. Herein, the identification and quantitation of pigment-related metabolites of SBF were studied for the first time, and the results provide a theoretical basis for understanding the pigment changes of jujube fruit during ripening.

12.
J Mass Spectrom ; 56(2): e4683, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33410198

RESUMEN

Benzylisoquinoline alkaloids (BIAs) have profound implications on human health owing to their potent pharmacological properties. Notable naturally occurring BIAs are the narcotic analgesics morphine, the cough suppressant codeine, the potential anticancer drug noscapine, the muscle relaxant papaverine, and the antimicrobial sanguinarine, all of which are produced in opium poppy (Papaver somniferum). Thebaine, an intermediate in the biosynthesis of codeine and morphine, is used in the manufacture of semisynthetic opiates, including oxycodone and naloxone. As the only commercial source of pharmaceutical opiates, opium poppy has been the focus of considerable research to understand BIA metabolism in the plant. The elucidation of several BIA biosynthetic pathways has enabled the development of synthetic biology platforms aimed at the alternative commercial production of valuable phytochemicals in microorganisms. The detection and identification of BIA pathway products and intermediates in complex extracts is essential for the continuing advancement of research in plant specialized metabolism and microbial synthetic biology. Herein, we report the use of liquid chromatography coupled with linear trap quadrupole and high-resolution Orbitrap multistage mass spectrometry to characterize 44 authentic BIAs using collision-induced dissociation (CID), higher-energy collisional dissociation (HCD), and pulsed Q collision-induced dissociation (PQD) MS2 fragmentation, with MS2 CID followed by MS3 and MS4 fragmentation. Our deep library of diagnostic spectral data constitutes a valuable resource for BIAs identification. In addition, we identified 22 BIAs in opium poppy latex and roots extracts.

13.
J Chromatogr A ; 1649: 462237, 2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34034106

RESUMEN

Herbs represent complex chemical systems involving various primary and secondary metabolites that are featured by large spans of acid-base property, polarity, molecular mass, and content, etc., which thus poses great challenges to characterize the metabolites contained. Here, the combination of multiple-mechanism chromatography coupled with improved data-dependent-MS2 acquisition (DDA-MS2) is presented as a strategy to support the deep metabolites characterization. Targeting Uncaria sessilifructus, a reputable medicinal herb containing alkaloids and triterpenic acids (TAs) as the main pharmacologically bioactive ingredients, a three-dimensional liquid chromatography (3D-LC) system was established by integrating ion exchange chromatography, hydrophilic interaction chromatography, and reversed-phase chromatography (IEC-HILIC-RPC). The first-dimensional chromatography, configuring a PhenoSphere SCX column eluted by methanol/20 mM ammonium acetate-0.05% formic acid in water, could well fractionate the total extract into two fractions (unretained ingredients and alkaloids). The subsequent HILIC using an XAmide column and RPC by a CSH Phenyl-Hexyl column achieved the sufficient resolution of the total TAs and total alkaloids, respectively. A polarity-switching precursor ions list-including DDA approach by Q-Orbitrap-MS enabled the high-efficiency, coverage-enhanced identification of alkaloids and TAs. This 3D-LC/Q-Orbitrap-MS system was validated as precise (RSD < 5% for intra-day/inter-day precision), Up to 308 components were separated from U. sessilifructus, and 128 thereof (including 85 alkaloids, 29 TAs, and 14 others) were identified or tentatively characterized, exhibiting superiority over the conventional one-dimensional LC/MS. Conclusively, 3D-LC/MS in an off-line mode can facilitate the flexible configuration of multiple chromatography to accomplish the fit-for-purpose characterization of the metabolites from an herbal extract or a biosample.


Asunto(s)
Cromatografía Liquida/métodos , Medicamentos Herbarios Chinos/química , Espectrometría de Masas/métodos , Uncaria/química , Alcaloides/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Peso Molecular , Triterpenos/análisis
14.
J Chromatogr A ; 1648: 462208, 2021 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-34000594

RESUMEN

Public exposure to pesticides through tobacco has attracted serious attention. Here we report a simultaneous screening and quantitation method for the non-target multiresidue analysis of pesticides in different tobacco types. The method involved extraction of a homogenate (20 g, containing 2 g tobacco) in ethyl acetate (10 mL), cleanup of 2 mL extract by dispersive solid phase extraction with PSA (50 mg)+C18 (50 mg)+GCB (25 mg)+MgSO4 (100 mg), followed by reconstitution in 1 mL acetonitrile:water (3:7) and analysis using HPLC with Quadrupole-Orbitrap mass spectrometry. The high resolution accurate mass analysis was performed through sequential full-scan (resolution=35000) and variable data independent acquisition (resolution=17500) events. When the method was evaluated in a mixture of 181 pesticides, it effectively minimised matrix interferences and false negatives. The target compounds included 5 pairs of isomers and 27 pairs of isobars, which were distinguished based on chromatographic separation, mass resolving power and/or unique product ions. The screening detection limit (SDL) for 86.4% of the test pesticides was set at 5 ng/g, while the remainder had the SDLs at 10 ng/g (9.3%) and 40 ng/g (4.3%). Nearly, 75% of the compounds showed recoveries of 70-120% at 10 ng/g. The rest of the compounds showed satisfactory recoveries at 40 and 100 ng/g. In all cases, precision-RSDs were < 20%. The established method demonstrated a successful performance in four different types of tobacco matrices while aligning with the guidelines of SANTE and US-FDA. Owing to its efficiency, the method is recommended for screening and quantitation of multiclass pesticides in tobacco.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Nicotiana/química , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Límite de Detección , Plaguicidas/análisis , Extracción en Fase Sólida/métodos , Productos de Tabaco/análisis
15.
Food Chem ; 356: 129643, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-33812190

RESUMEN

A rapid screening method of 70 colorants for regulatory control in dyeable foods was established using ultra-high-performance liquid chromatography-hybrid quadrupole-Orbitrap mass spectrometry (UHPLC-Q/Orbitrap MS) with customized accurate-mass database and mass spectral library. A rapid, high-throughput, and simple sample pretreatment condition with low reagent consumption and high recovery was developed on the basis of ultrasound-assisted extraction and dispersion solid-phase extraction. Rapid screening was conducted by comparing the experimentally measured exact mass of the parent and fragment ions, the isotope pattern, and the retention time with the accurate-mass database and by matching the acquired MS/MS spectra against the mass spectral library. The performance of the method was evaluated in terms of linearity, limits of detection, limits of quantitation, recovery, repeatability, reproducibility, and matrix effect. The proposed method was applied for simultaneous analysis of 70 colorants in seven kinds of dyeable foods, and it exhibited great potential for broad, sensitive, and reliable.


Asunto(s)
Colorantes de Alimentos/química , Cromatografía Líquida de Alta Presión , Bases de Datos Factuales , Alimentos , Límite de Detección , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Espectrometría de Masas en Tándem , Factores de Tiempo
16.
Drug Test Anal ; 13(6): 1127-1135, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33554459

RESUMEN

In recent years, diphenidol [1,1-diphenyl-4-piperidino-1-butanol] has been one of the drugs that appears in suicide cases, but there are few research data on its metabolic pathways and main metabolites. Metabolite identification plays a key role in drug safety assessment and clinical application. In this study, in vivo and in vitro samples were analyzed with ultra-high-performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry. Structural elucidation of the metabolites was performed by comparing their molecular weights and product ions with those of the parent drug. As a result, 10 Phase I metabolites and 5 glucuronated Phase II metabolites were found in a blood sample and a urine sample from authentic cases. Three other Phase I metabolites were identified in the rat liver microsomes incubation solution. The results showed that the main metabolic pathways of diphenidol in the human body include hydroxylation, oxidation, dehydration, N-dealkylation, methylation, and conjugation with glucuronic acid. This study preliminarily clarified the metabolic pathways and main metabolites of diphenidol. For the development of new methods for the identification of diphenidol consumption, we recommend using M2-2 as a marker of diphenidol entering the body. The results of this study provide a theoretical basis for the pharmacokinetics and forensic scientific research of diphenidol.


Asunto(s)
Antieméticos/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Piperidinas/metabolismo , Animales , Antieméticos/análisis , Humanos , Masculino , Microsomas Hepáticos/metabolismo , Piperidinas/análisis , Ratas , Ratas Sprague-Dawley , Especificidad de la Especie
17.
J Pharm Biomed Anal ; 206: 114385, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34597841

RESUMEN

Kai-Xin-San (KXS) is a traditional Chinese medicine (TCM) formula containing four herbal medicines: Ginseng Radix Rhizoma, Polygalae Radix, Poria and Acori Tatarinowii Rhizoma. A large number of pharmacological studies in vitro and in vivo have shown that KXS is characterized by anti-depression, anti-Alzheimer's disease, anti-oxidation and other activities. However, the pharmacodynamic substance basis studies of KXS are hitherto quite limited. Here, KXS was identified and determined by ultra-performance liquid chromatography-quadrupole-Orbitrap mass spectrometry (UPLC-Q-Orbitrap MS) and gas chromatography-mass spectrometry (GC-MS). Firstly, the data-dependent acquisition mode (DDA) of UPLC-Q-Orbitrap MS combined with the inclusion list were used to collected the chemical composition. The chemical constituents of KXS were identified by local database on compound discoverer™ 3.1 software and Xcalibur 4.1 software. With the use of this approach, a total of 211 compounds were identified from KXS. Wherein 60 compounds were from Ginseng Radix Rhizoma, 40 compounds were from Poria, and 111 compounds were from Polygala Radix, respectively. Secondly, 105 volatile constituents were identified by GC-MS analysis, which were mainly derived from Acori Tatarinowii Rhizoma. Besides, an adjusted parallel reaction monitoring method was established and validated to quantify the seventeen major compounds in different herbal medicines of KXS, which were chosen as the benchmarked substances to evaluate the quality of KXS. In conclusion, this study provided a generally applicable strategy for global metabolite identification of the complicated components and determination of multi-component content in traditional Chinese medicines.


Asunto(s)
Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas
18.
Water Res ; 195: 117000, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33721679

RESUMEN

Mature landfill leachate contains a substantial fraction of recalcitrant dissolved organic matters (DOM) that is a challenging for conventional wastewater treatment that is typically focused on the removal of biodegradable organic matter. "Biological treatment + membrane treatment" has been widely employed to treat complex leachate. However, the performance of each unit based on both conventional bulk indicators and molecular information has not been well understood. Therefore, the fate of DOM chemodiversity along the full-scale treatment process across ten sampling points over three different seasons were analyzed to determine the efficiency of every unit process with the assistance of ultra-performance liquid chromatography coupled with hybrid quadrupole Orbitrap mass spectrometry. Results showed that the process performance, visualized through the molecular signals, were relatively stable in the temporal dimension. The process removed 83.2%-92.2% of DOM molecules in terms of richness, where lignin/carboxyl-rich alicyclic compounds (CRAM)-likes with relatively high saturation was preferentially removed, while newly generated bio-derived N-containing compounds (N/Cwa 0.15-0.17) became resistant. The relationship between conventional bulk physicochemical indicators and molecular indexes suggested that soluble chemical oxygen demand (sCOD) and dissolved organic carbon (DOC) were contributed by the refractory DOM with high weighted average double bond equivalents (DBEwa), which was distributed in the region of O/C 0.2-0.5 and H/C 1.2-1.8. This refractory DOM required ultrafiltration and nanofiltration for removal. DOM molecules were positively correlated with five-day biochemical oxygen demand (BOD5) and revealed that approximately 96.9%-98.4% of the DOM could be removed or transformed in the primary anoxic zone. In addition, the bio-derived aliphatic/proteins, lipids and lignin/CRAM-likes (O/C > 0.2) with condensed aromatization were the sources of dissolved organic nitrogen (DON) and still remained in the final effluent. The present study suggests that the design and operation of the combination process with biological and membrane treatment could be specifically optimized based on the DOM molecular characteristics of the wastewater.


Asunto(s)
Contaminantes Químicos del Agua , Carbono , Compuestos Orgánicos , Ultrafiltración , Aguas Residuales
19.
Methods Mol Biol ; 1647: 61-69, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28808995

RESUMEN

With the advent of new methodologies, proteomics-based assays are increasingly used to study the efficacy of drugs on a molecular level. For these studies to be meaningful, the proteomics assays need to be sensitive, selective, accurate, and reproducible. This is often accomplished through a targeted approach, either using single or multiple reaction monitoring (SRM/MRM) or, more recently, parallel reaction monitoring (PRM). In PRM, the parallel detection of all product ions in a high-resolution mass spectrometer affords higher selectivity than SRM/MRM. PRM is thus better suited to analyze peptides larger than 2 kDa. Similar to SRM/MRM, PRM provides sensitive, accurate, and reproducible quantitative data. Here, we present a specific PRM method to characterize the effects of histone modifying enzyme drugs such as histone deacetylase inhibitors (HDAC) on the posttranslational modifications of histones, in a quantitative manner. More specifically, we characterize the heavily modified N-terminal tail of histone H3 after treatment with the HDAC inhibitor butyric acid, and monitor the acetylation and methylation events after treatment. To take most advantage of the multiply charged N-terminal histone peptides that are generated by an endoproteinase GluC-digestion, we use electron transfer dissociation (ETD) as the method of MS/MS fragmentation. This provides high sequence coverage for the modified peptides. The methodology is not limited to HDAC inhibitors, and can be used for any modifying enzyme. In fact, it can even be expanded beyond histone analyses. To give guidance for the development of a PRM assay, we present here HDAC inhibited H3 histone N-terminal tails as an example.


Asunto(s)
Activadores de Enzimas/farmacología , Código de Histonas/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Histonas/metabolismo , Proteómica/métodos , Acetilación/efectos de los fármacos , Ácido Butírico/farmacología , Transporte de Electrón , Iones , Espectrometría de Masas , Metilación/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Journal of Forensic Medicine ; (6): 473-477, 2022.
Artículo en Inglés | WPRIM | ID: wpr-984138

RESUMEN

OBJECTIVES@#To establish a method to identify unknown sample based on the combined use of Fourier transform infrared spectroscopy (FTIR), gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry (UPLC-LTQ-Orbitrap MS) and 1H-nuclear magnetic resonance spectroscopy (1H-NMR) technique.@*METHODS@#The unknown sample was directly analyzed by FTIR. The unknown sample was dissolved in methanol solution containing internal standard SKF525A and the supernatant was detected by GC-QTOF-MS and UPLC-LTQ-Orbitrap MS. The unknown sample was dissolved in methanol-d4 solution for structural analysis of 1H-NMR.@*RESULTS@#The characteristic absorption peaks of FTIR spectra obtained from unknown sample were 1 682 (C=O bond), 1 503, 1 488, 1 436, 1 363, 1 256, 1 092, 1 035, 935, 840 and 800 cm-1, the characteristic fragment ions (m/z) of GC-QTOF-MS were 86.096 4 (base peak), 58.065 1, 149.023 5, 121.028 6 and 65.038 6, the accurate mass [M+H]+ detected by UPLC-LTQ-Orbitrap MS was 236.127 7. The sample was identified as synthetic cathinone new psychoactive substance Eutylone by 1H-NMR.@*CONCLUSIONS@#The method established in this study can be used for structural confirmation of Eutylone.


Asunto(s)
Metanol , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectroscopía de Resonancia Magnética
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