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1.
Molecules ; 28(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37894534

RESUMO

A rapid and sensitive method that combined ultra-high-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry (UHPLC-FT-ICR-MS) was used to identify the chemical constituents in Lanqin oral liquid. On the basis of UHPLC-FT-ICR-MS analysis, systematic characterization of the chemical profile of Lanqin oral liquid was carried out, and a total of 441 compounds were identified or tentatively characterized including alkaloids, flavonoids, terpenoids, organic acids, phenylpropanoids, and other types. The results provide a reference for improving quality control, contribute to establishing higher quality standards, provide a scientific basis for further research on the pharmacodynamic material basis, and help illustrate the relationship between the complicated constituents and therapeutic effects of Lanqin oral liquid.


Assuntos
Ciclotrons , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Análise de Fourier , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas/métodos
2.
Phytochem Anal ; 34(8): 1009-1021, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37518673

RESUMO

INTRODUCTION: Dahlia pinnata Cav. is a flower native to Mexico that has many applications; in particular, its petals have been used for ornamental, food, and medicinal purposes, for example to treat skin rashes and skin cracks. It has been reported that the medicinal properties of plants are generally related to the phytochemical constituents they possess. However, there are few studies on black D. pinnata. OBJECTIVES: The present study was aimed at qualitatively and quantitatively determining the phytochemical profile of petals from black D. pinnata. METHODOLOGY: Phytochemicals from Dahlia petals were extracted by consecutive maceration (hexane, dichloromethane, and methanol); then, the extracts were analyzed through colorimetric assays and UV-Vis spectroscopy for qualitative identification and quantification of phytochemical compounds, respectively. The methanolic extract was analyzed by flow injection analysis-electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry (FIA-ESI-FTICR-MS) in negative and positive mode. RESULTS: Quantitative phytochemical profiling of the methanolic extract by UV-Vis spectroscopy indicated high contents of phenolic compounds (34.35 ± 3.59 mg EQ/g plant) and sugars (23.91 ± 1.99 mg EQ/g plant), while the qualitative profiling by FIA-ESI-FTICR-MS allowed the tentative identification of several flavonoids and phenolic acids. Kaempferol-3-rutinoside, pelargonidin-3-(6″-malonylglucoside)-5-glucoside, rutin, kaempferol-3-(2″,3″-diacetyl-4″-p-coumaroylrhamnoside), and myricetin-3-(2‴-galloylrhamnoside) were the main compounds detected. CONCLUSION: The results expand our knowledge of the phytochemical constituents of petals from black D. pinnata.


Assuntos
Dahlia , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Quempferóis , Ciclotrons , Análise de Injeção de Fluxo , Análise de Fourier , Extratos Vegetais/química , Metanol , Compostos Fitoquímicos/análise
3.
Food Chem ; 403: 134404, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182850

RESUMO

Roasting is a technological process in some food applications of agricultural products. To investigate the composition changes of the extractable functional/bioactive components of cottonseed, in this work, glandless cottonseed kernels were roasted at 110, 120, 140 and 150 °C for 15 min, respectively. The UV/vis data of the 80 % ethanol extracts found that roasting increased the level of phenolic compounds. Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry of the extracts identified about 44 % to 55 % of total formulas as potential phenolic compounds. Roasting (up to 140 °C) mainly increased carbohydrate-, lignin-, and tannin-like compounds while lipid-like compounds decreased. The compositional changes at 150 °C were less than those at 140 °C, attributed to devolatilization at the higher temperature. The information of chemical profiling of cottonseed and the roasting impact would be greatly useful in enhanced utilization of cottonseed as nutrient and functional foods or food supplements.


Assuntos
Óleo de Sementes de Algodão , Ciclotrons , Óleo de Sementes de Algodão/química , Análise de Fourier , Espectrometria de Massas/métodos , Lignina , Espectrometria de Massas por Ionização por Electrospray/métodos
4.
Anal Chem ; 94(42): 14537-14545, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36215705

RESUMO

We present a detailed molecular characterization of organophosphorus compounds in ambient organic aerosol influenced by wildfire smoke. Biomass burning organic aerosol (BBOA) is an important source of phosphorus (P) to surface waters, where even a small imbalance in the P flux can lead to substantial effects on water quality, such as eutrophication, algal blooms, and oxygen depletion. We aimed to exploit the ultrahigh resolving power, mass accuracy, and sensitivity of Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS) to explore the molecular composition of an ambient BBOA sample collected downwind of Pacific Northwest wildfires. The 21-T FT-ICR MS yielded 10 533 distinct formulae, which included molecular species comprising C, H, O, and P with or without N, i.e., organophosphorus compounds that have long been quantified in wildfire smoke but have not yet been characterized at the molecular level. The lack of detailed molecular characterization of organophosphorus compounds in BBOA is primarily due to their inherently low concentrations in aerosols and poor ionization efficiency in complex mixtures. We demonstrate that the exceptional sensitivity of the 21-T FT-ICR MS allows qualitative analysis of a previously uncharacterized fraction of BBOA without its selective concentration from the organic matrix, exemplifying the need for ultrahigh-resolution tools for a more detailed and accurate molecular depiction of such complex mixtures.


Assuntos
Ciclotrons , Incêndios Florestais , Análise de Fourier , Fumaça , Compostos Organofosforados , Espectrometria de Massas/métodos , Aerossóis , Fósforo , Oxigênio
5.
Environ Sci Technol ; 56(18): 12988-12998, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36041117

RESUMO

Pavement sealants are of environmental concern because of their complex petroleum-based chemistry and potential toxicity. Specifically, coal tar-derived sealants contain high concentrations of toxic/carcinogenic polycyclic aromatic hydrocarbons (PAHs) that, when weathered, can be transferred into the surrounding environment. Previous studies have demonstrated the effects of coal tar sealants on PAH concentration in nearby waterways and their harmful effects in aquatic ecosystems. Here, we investigate and compare the molecular composition of two different pavement sealants, petroleum asphalt- and coal tar-derived, and their photoproducts, by positive-ion (+) atmospheric pressure photoionization (APPI) and negative-ion (-) electrospray ionization (ESI) coupled with ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry to address species (high-boiling and/or high oxygen content) that lie outside the analytical window of other techniques due to ultra-high molecular complexity. In addition, we evaluate the toxicity of the water-soluble photoproducts by use of Microtox bioassay. The results demonstrate that the coal tar sealant contains higher amounts of PAHs and produces abundant water-soluble compounds, relative to unweathered materials, with a high abundance of PAH-like molecules of high toxicity. By comparison, the asphalt sealant produces fewer toxic water-soluble species, with molecular compositions that are consistent with natural dissolved organic matter. These results capture the mass, chemical diversity, toxicity, and source/photoproduct relationship of these compositionally complex emerging contaminants from the built environment.


Assuntos
Alcatrão , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Alcatrão/química , Alcatrão/toxicidade , Ciclotrons , Ecossistema , Análise de Fourier , Hidrocarbonetos , Espectrometria de Massas , Oxigênio/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Água
6.
Med Phys ; 49(4): 2709-2724, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35134261

RESUMO

PURPOSE: 64 Cu and 67 Cu radioisotopes have nuclear characteristics suitable for nuclear medicine applications. The production of 64 Cu is already well established. However, the production of 67 Cu in quantities suitable to conduct clinical trials is more challenging as it leads to the coproduction of other Cu isotopes, in particular 64 Cu. The aim of this study is to investigate the possibility of using a CuCl2 solution with a mixture of 67/64 Cu radioisotopes for therapeutic purposes, providing an alternative solution for the cyclotron production problem. METHODS: Copper radioisotopes activities were calculated by considering proton beam irradiation of the following targets: (i) 70 Zn in the energy range 70-45 MeV; (ii) 68 Zn in the energy range 70-35 MeV; (iii) a combination of 70 Zn (70-55 MeV) and 68 Zn (55-35 MeV). The contribution of each copper radioisotope to the human-absorbed dose was estimated with OLINDA/EXM software using the biokinetic model for CuCl2 published by ICRP 53. The total absorbed dose generated by the 67/64 CuCl2 mixture, obtained through different production routes, was calculated at different times after the end of the bombardment (EOB). A simple spherical model was used to simulate tumors of different sizes containing uniformly distributed 67/64 Cu mixture and to calculate the absorbed dose of self-irradiation. The biological damage produced by 67 Cu and 64 Cu was also evaluated through cellular dosimetry and cell surviving fraction assessment using the MIRDcell code, considering two prostate cancer cell lines with different radiosensitivity. RESULTS: The absorbed dose to healthy organs and the effective dose (ED) per unit of administered activity of 67 CuCl2 are higher than those of 64 CuCl2 . Absorbed dose values per unit of administered activity of 67/64 CuCl2 mixture increase with time after the EOB because the amount of 67 Cu in the mixture increases. Survival data showed that the biological damage caused per each decay of 67 Cu is greater than that of 64 Cu, assuming that radionuclides remain accumulated in the cell cytoplasm. Sphere model calculations demonstrated that 64 Cu administered activity must be about five times higher than that of 67 Cu to obtain the same absorbed dose for tumor mass between 0.01 and 10 g and about 10 times higher for very small spheres. Consequently, the 64 CuCl2 -absorbed dose to healthy organs will reach higher values than those of 67 CuCl2 . The supplemental activity of the 67/64 CuCl2 mixture, required to get the same tumor-absorbed dose produced by 67 CuCl2 , triggers a dose increment (DI) in healthy organs. The waiting time post-EOB necessary to keep this DI below 10% (t10% ) depends on the irradiation methods employed for the production of the 67/64 CuCl2 mixture. CONCLUSIONS: A mixture of cyclotron produced 67/64 Cu radioisotopes proved to be an alternative solution for the therapeutic use of CuCl2 with minimal DI to healthy organs compared with pure 67 Cu. Irradiation of a 70 Zn+68 Zn target in the 70-35 MeV proton energy range for 185 h appears to be the best option from among all the production routes investigated, as it gives the maximum amount of activity, the shortest t10% (10 h), and less than 1% of 61 Cu and 60 Cu impurities.


Assuntos
Ciclotrons , Neoplasias , Radioisótopos de Cobre , Estudos de Viabilidade , Humanos , Masculino , Neoplasias/tratamento farmacológico , Prótons , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos
7.
J Sep Sci ; 45(6): 1185-1194, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35014761

RESUMO

Alpiniae Oxyphyllae Fructus, as a homology of medicine and food, has been widely used in China for thousands of years. However, the existing qualitative and quantitative methods are difficult to evaluate the quality of Alpiniae Oxyphyllae Fructus samples from multiple sources. In this paper, an high-performance liquid chromatography fingerprint was established for assessing the quality of Alpiniae Oxyphyllae Fructus from different areas. Then, high-performance liquid chromatography was coupled to Fourier transform-ion cyclotron resonance mass spectrometry for characterization of the chemical compositions in Alpiniae Oxyphyllae Fructus. In fingerprint analysis, 54 common peaks were confirmed and six chromatographic peaks of them were identified. The similarity of 14 samples from different areas was between 0.990 and 1.000. Moreover, a total of 30 chemical components were characterized by high-performance liquid chromatography coupled to Fourier transform-ion cyclotron resonance mass spectrometry method, six compounds of which were decisively identified. Finally, the content of nootkatone was determined by high-performance liquid chromatography. In conclusion, the methods used in this study are efficient for qualitative and quantitative analysis of Alpiniae Oxyphyllae Fructus. Also, these methods can be used to control the quality of other traditional Chinese medicines.


Assuntos
Ciclotrons , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Análise de Fourier , Frutas/química , Espectrometria de Massas
8.
Mass Spectrom Rev ; 41(5): 647-661, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-32412674

RESUMO

Among the different techniques for mass analysis, ultra-high-resolution Fourier transform ion cyclotron resonance (FTICR) is the method of choice for highly complex samples, as it offers unrivaled mass accuracy and resolving power, combined with a high degree of flexibility in hybrid instruments as well as for ion activation techniques. FTICR instruments are readily embraced by the biological and biomedical research communities and applied over a wide range of applications for the analysis of biomolecules such as carbohydrates, lipids, nucleic acids, and proteins. In the field of natural organic matter (NOM) analysis, petroleum-related studies currently dominate FTICR-MS applications. Recently, however, there is a growing interest in developing high-performance MS methods for the characterization of NOM samples from natural aquatic and terrestrial environments. Here, we present an overview of FTICR-MS techniques for complex, non-petroleum NOM samples, including data analysis and novel tandem mass spectrometry (MS/MS) methods for structural classifications. © 2020 The Authors. Mass Spectrometry Reviews published by John Wiley & Sons Ltd.


Assuntos
Ciclotrons , Petróleo , Análise de Fourier , Íons , Proteínas/química , Espectrometria de Massas em Tandem
9.
J Sep Sci ; 45(2): 477-491, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34741585

RESUMO

Alcoholic liver disease is currently the most clinically concerning liver disease, which occurs from chronic alcohol abuse. Flos Puerariae and Semen Hoveniae have been used to treat alcohol drinking excessively for thousands of years in China. In this study, the ethanol extract of the medicine pair was qualitatively and quantitatively analyzed by high-performance liquid chromatography and Fourier transform ion cyclotron resonance mass spectrometry. First, the high-performance liquid chromatography fingerprint was established to obtain the overall chromatographic data of its chemical constituents. Next, high-performance liquid chromatography-mass spectrometry was applied to identify its chemical constituents. Then, the characteristic constituents were simultaneously quantified by high-performance liquid chromatography. In addition, the chemical constituents that were absorbed into rat plasma were identified by high-performance liquid chromatography-mass spectrometry. As a result, a total of 48 chemical constituents in the medicine pair were detected and identified in vitro. Meanwhile, the content of seven representative constituents, including dihydromyricetin, glycitin, genistin, tectoridin, glycitein, genistein, and tectorigenin were simultaneously determined. Furthermore, a total of 19 chemical constituents were detected in rat plasma after oral administration. In short, the chemical constituents of the medicine pair were initially investigated in this study, which will lay the foundation for the discovery of its pharmacodynamic substances in further works.


Assuntos
Medicamentos de Ervas Chinesas , Pueraria , Animais , Cromatografia Líquida de Alta Pressão/métodos , Ciclotrons , Medicamentos de Ervas Chinesas/análise , Análise de Fourier , Espectrometria de Massas/métodos , Pueraria/química , Ratos , Sementes/química
10.
Anal Chem ; 93(41): 13749-13754, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34623794

RESUMO

High magnetic field Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry provides the highest mass resolving power and mass measurement accuracy for detailed characterization of complex chemical mixtures. Here, we report the coupling of online liquid chromatography of complex mixtures with a 21 tesla FT-ICR mass spectrometer. The high magnetic field enables large ion populations to be analyzed for each spectrum for a high dynamic range, with 3.2 million mass resolving power at m/z 400 (6.2 s transient duration) or 1.6 million (3.1 s transient duration) while maintaining high mass accuracy for molecular formula assignment (root-mean-square assignment error < 0.150 ppm). Thousands of unique elemental compositions are assigned per mass spectrum, which can be grouped by the heteroatom class, double bond equivalents (the number of rings and double bonds to carbon), and carbon number. Figures of merit are discussed, as well as characterization of an Arabian heavy vacuum gas oil in terms of the ring number, compound class, double bond equivalents, and ion type. Consideration of elemental composition and retention order provides additional structural information.


Assuntos
Ciclotrons , Petróleo , Cromatografia Líquida , Análise de Fourier , Espectrometria de Massas , Petróleo/análise
11.
Med Phys ; 48(8): 4472-4484, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34077590

RESUMO

PURPOSE: The purpose of this work is to (a) demonstrate the feasibility of delivering a spread-out Bragg peak (SOBP) proton beam in ultra-high dose rate (FLASH) using a proton therapy synchrocyclotron as a major step toward realizing an experimental platform for preclinical studies, and (b) evaluate the response of four models of ionization chambers in such a radiation field. METHODS: A clinical Mevion HYPERSCAN® synchrocyclotron was adjusted for ultra-high dose rate proton delivery. Protons with nominal energy of 230 MeV were delivered in pulses with temporal width ranging from 12.5 µs to 24 µs spanning from conventional to FLASH dose rates. A boron carbide absorber and a range modulator block were placed in the beam path for range modulation and creating an SOBP dose profile. The radiation field was defined by a brass aperture with 11 mm diameter. Two Faraday cups were used to determine the number of protons per pulse at various dose rates. The dosimetric response of two cylindrical (IBA CC04 and CC13) and two plane-parallel (IBA PPC05 and PTW Advanced Markus® ) ionization chambers were evaluated. The dose rate was measured using the plane-parallel ionization chambers. The integral depth dose (IDD) was measured with a PTW Bragg Peak® ionization chamber. The lateral beam profile was measured with EBT-XD radiochromic film. Monte Carlo simulation was performed in TOPAS as the secondary check for the measurements and as a tool for further optimization of the range modulators' design. RESULTS: Faraday cups measurement showed that the maximum protons per pulse is 39.9 pC at 24 µs pulse width. A good agreement between the measured and simulated IDD and lateral beam profiles was observed. The cylindrical ionization chambers showed very high ion recombination and deemed not suitable for absolute dosimetry at ultra-high dose rates. The average dose rate measured using the PPC05 ionization chamber was 163 Gy/s at the pristine Bragg peak and 126 Gy/s at 1 cm depth for the SOBP beam. The SOBP beam range and modulation were measured 24.4 mm and 19 mm, respectively. The pristine Bragg peak beam had 25.6 mm range. Simulation results showed that the IDD and profile flatness can be improved by the cavity diameter of the range modulator and the number of scanned spots, respectively. CONCLUSIONS: Feasibility of delivering protons in an SOBP pattern with >100 Gy/s average dose rate using a clinical synchrocyclotron was demonstrated. The dose heterogeneity can be improved through optimization of the range modulator and number of delivered spots. Plane-parallel chambers with smaller gap between electrodes are more suitable for FLASH dosimetry compared to the other ion chambers used in this work.


Assuntos
Terapia com Prótons , Prótons , Ciclotrons , Método de Monte Carlo , Radiometria , Dosagem Radioterapêutica
12.
J Pharm Biomed Anal ; 198: 114022, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33744466

RESUMO

Yinchen Wuling Powder (YCWLP) is a classic Chinese medicine prescription with a long history and has been commonly used for treating jaundice hepatitis, liver fibrosis, hyperlipidemia and early diabetes in clinical applications. However, the chemical composition of YCWLP is still unclear. In order to obtain the chemical profile of YCWLP, a systematic ultra-performance liquid chromatography coupled with fourier transform ion cyclotron resonance mass spectrometry (UPLC-FT-ICR-MS) method was developed in this study. As a result, a total of 138 compounds including terpenoid acids, organic acids, flavonoids, sesquiterpenes, coumarins and anthraquinones were identified by comparing the retention time, molecular ions and fragmentation behaviors with the reference compounds or the in-house database. This study comprehensively elucidated the chemical basis of YCWLP and provided a scientific basis for further quality control and pharmacology research.


Assuntos
Ciclotrons , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Análise de Fourier , Espectrometria de Massas , Pós
13.
J Sep Sci ; 43(24): 4434-4460, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33108700

RESUMO

Duzhong Jiangya tablet is a hypotensive drug. In this study, high-performance liquid chromatography-Fourier transform-ion cyclotron resonance-mass spectrometry technology was used to quickly identify its chemical composition. SinoChrom ODS-BP column (250 mm × 4.6 mm, 5 µm) was used. The mobile phase was acetonitrile(A)-0.1% formic acid solution(B). The flow rate was 1 mL/min. Extracted ion chromatogram was used to analyze the samples in positive and negative ion modes. Based on the accurate mass spectrometry information (such as quasi-molecular ions and fragment ions) obtained from the instrument, combined with reference compounds and literature, the chemical composition of Duzhong Jiangya Tablets was identified. A total of 131 compounds were identified, including four types of penylpropanoids, six types of phenylethanoid glycosides, 10 types of organic acids, 14 types of iridoids, 12 types of lignans, 18 types of alkaloids, seven types of coumarins, and 60 kinds of flavonoids. This established method can quickly and efficiently identify chemical constituents in Duzhong Jiangya tablet, lay a foundation for the research on the efficacy and quality of this traditional Chinese medicine, and provide a reference for the characterization of the chemical constituents of other traditional Chinese medicine preparations.


Assuntos
Medicamentos de Ervas Chinesas/análise , Cromatografia Líquida de Alta Pressão , Ciclotrons , Análise de Fourier , Espectrometria de Massas , Estrutura Molecular , Comprimidos
14.
Nucl Med Rev Cent East Eur ; 22(2): 56-59, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482557

RESUMO

BACKGROUND: 44Sc is becoming attractive as a PET radionuclide due to its decay characteristics. It can be produced from 44Ca present in natural calcium with 2.08% abundance. MATERIALS AND METHODS: The targets were mostly prepared from natural CaCO3 or metallic calcium in the form of pellets. After irradiation they were dissolved in 3 M hydrochloric acid and 44Sc was separated from excess of calcium by precipitation of scandium hydroxide using ammonia. Alternatively, targets were dissolved in 11 M hydrochloric acid and 44Sc was separated by extraction chromatography on UTEVA resin. As the next step, in both processes 44Sc was further purified on a cation exchange resin. Initially, the separation procedures were developed with 46Sc as a tracer. Gamma spectrometry with a high purity germanium detector was used to determine the separation efficiency. Finally, the CaCO3 pellet with 99.2% enrichment in 44Ca was activated with protons via 44Ca(p,n)44Sc nuclear reaction. RESULTS: Altogether twenty two irradiations and separations were performed. The working procedures were developed and the quality of separated 44Sc solution was confirmed by radiolabeling of DOTATATE. The chemical purity of the product was sufficient for preclinical experiments. At the end of around 1 hour proton beam irradiation of CaCO3 pellet with 99.2% enrichment in 44Ca the obtained radioactivity of 44Sc was more than 4.8 GBq. CONCLUSION: 44Sc can be produced inexpensively with adequate yields and radionuclidic purity via 44Ca(p,n)44Sc nuclear reaction in small cyclotrons. The recovery yield in both investigated separation methods was comparable and amounted above 90%. The obtained 44Sc was pure in terms of radionuclide and chemical purity, as shown by the results of peptide radiolabeling.


Assuntos
Elementos da Série Actinoide/química , Precipitação Química , Hidróxidos/química , Radioquímica/métodos , Radioisótopos/química , Radioisótopos/isolamento & purificação , Escândio/química , Escândio/isolamento & purificação , Urânio/química , Carbonato de Cálcio/química , Ciclotrons , Marcação por Isótopo , Radioquímica/instrumentação
15.
Environ Sci Technol ; 53(12): 6887-6894, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31149817

RESUMO

We present a solid-phase extraction method followed by derivatization with a charged tag to characterize ketone/aldehyde-containing functionalities (proposed photo-oxidation transformation products) in weathered petroleum by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). A photo-oxidation-only microcosm mimics solar irradiation of crude oil in the environment after an oil spill. A biodegradation-only microcosm enables independent determination as to which of the two weathering processes contributes to the formation of oil-soluble ketone/aldehyde species. Results confirm that photo-oxidation produces ketones/aldehydes in crude oil when exposed to solar radiation in laboratory experiments, whereas biodegraded oil samples do not produce ketone/aldehyde compounds. Field samples collected after different time periods and locations after the Deepwater Horizon oil spill are also shown to contain ketones/aldehydes, and comparison of field and photo-oxidation-only microcosm transformation products reveal remarkable similarity. These results indicate that the photo-oxidation microcosm comprehensively represents ketone/aldehyde-formation products in the field, whereas the biodegradation microcosm does not. Solid-phase extraction coupled with derivatization leads to selective identification of ketone/aldehyde species by MS. Although improved dynamic range and slightly reduced mass spectral complexity is achieved by separation/derivatization, comprehensive molecular characterization still requires mass resolving power and mass accuracy provided by FT-ICR MS.


Assuntos
Ciclotrons , Petróleo , Aldeídos , Análise de Fourier , Cetonas , Espectrometria de Massas
16.
Environ Sci Technol ; 52(3): 1365-1374, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29320168

RESUMO

We report chemical characterization of natural oil seeps from the Gulf of Mexico by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and Gas Chromatography/Atmospheric Pressure Chemical Ionization Mass Spectrometry (GC/APCI-MS), to highlight how FT-ICR MS can also be employed as a means to determine petroleum connectivity, in addition to traditional GC/MS techniques. The source of petroleum is the Green Canyon (GC) 600 lease block in the Gulf of Mexico. Within GC600, two natural oil seepage zones, Mega Plume and Birthday Candles, continuously release hydrocarbons and develop persistent oil slicks at the sea surface above them. We chemically trace the petroleum from the surface oil slicks to the Mega Plume seep itself, and further to a petroleum reservoir 5 km away in lease block GC645 (Holstein Reservoir). We establish the connectivity between oil samples and confirm a common geological origin for the oil slicks, oil seep, and reservoir oil. The ratios of seven common petroleum biomarkers detected by GC/APCI-MS display clear similarity between the GC600 and GC645 samples, as well as a distinct difference from another reservoir oil collected ∼300 km away (Macondo crude oil from MC252 lease block). FT-ICR MS and principal component analysis (PCA) demonstrate further similarities between the GC600 and GC645 samples that distinctly differ from MC252. A common geographical origin is postulated for the GC600/GC645 samples, with petroleum migrating from the GC645 reservoir to the oil seeps found in GC600 and up through the water column to the sea surface as an oil slick.


Assuntos
Ciclotrons , Petróleo , Análise de Fourier , Cromatografia Gasosa-Espectrometria de Massas , Golfo do México , Espectrometria de Massas
17.
J Sep Sci ; 41(3): 774-788, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29131518

RESUMO

In this study, a reliable and sensitive ultra-high performance liquid chromatography coupled with fourier transform ion cyclotron resonance mass spectrometry method was developed for the systematic study of the metabolic profile of Kudiezi injection in rat plasma, bile, urine, and feces after intravenous administration of a single dose. The chromatographic separation was performed on an Agilent Eclipse Plus C18 column (4.6 mm × 50 mm, 1.8 µm) and the identification of prototype components and metabolites was achieved on a Bruker Solarix 7.0 T ultra-high resolution spectrometer in negative ion mode. Results indicated that a total of 76 constituents including 29 prototype compounds and 47 metabolites (10 phase I metabolites and 37 phase II metabolites) were tentatively identified. And the metabolic pathways of these prototype compounds including hydroxylation, dehydrogenation, glucuronidation, and sulfate conjugation. In conclusion, the developed method with high resolution and sensitivity was effective for screening and identification of prototypes and metabolites of Kudiezi injection in vivo. Moreover, these results would provide significant information for further pharmacokinetic and pharmacological research of Kudiezi injection in vivo.


Assuntos
Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Análise de Fourier , Espectrometria de Massas , Metaboloma , Animais , Bile/química , Ciclotrons , Fezes/química , Hidrólise , Hidroxilação , Injeções , Masculino , Plasma/química , Ratos , Ratos Sprague-Dawley , Urina/química
18.
J Cancer Res Ther ; 13(3): 456-465, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28862209

RESUMO

AIMS: The reactor has increased its area of application into medicine especially boron neutron capture therapy (BNCT); however, accelerator-driven neutron sources can be used for therapy purposes. The present study aimed to discuss an alternative method in BNCT functions by a small cyclotron with low current protons based on Karaj cyclotron in Iran. MATERIALS AND METHODS: An epithermal neutron spectrum generator was simulated with 30 MeV proton energy for BNCT purposes. A low current of 300 µA of the proton beam in spallation target concept via 9Be target was accomplished to model neutron spectrum using 208Pb moderator around the target. The graphite reflector and dual layer collimator were planned to prevent and collimate the neutrons produced from proton interactions. Neutron yield per proton, energy distribution, flux, and dose components in the simulated head phantom were estimated by MCNPX code. RESULTS: The neutron beam quality was investigated by diverse filters thicknesses. The maximum epithermal flux transpired using Fluental, Fe, Li, and Bi filters with thicknesses of 7.4, 3, 0.5, and 4 cm, respectively; as well as the epithermal to thermal neutron flux ratio was 161. Results demonstrated that the induced neutrons from a low energy and low current proton may be effective in tumor therapy using 208Pb moderator with average lethargy and also graphite reflector with low absorption cross section to keep the generated neutrons. CONCLUSIONS: Combination of spallation-based BNCT and proton therapy can be especially effective, if a high beam intensity cyclotron becomes available.


Assuntos
Terapia por Captura de Nêutron de Boro/métodos , Neoplasias/radioterapia , Nêutrons/uso terapêutico , Berílio/química , Berílio/uso terapêutico , Ciclotrons , Humanos , Irã (Geográfico) , Método de Monte Carlo , Imagens de Fantasmas , Terapia com Prótons
19.
J Sep Sci ; 40(16): 3188-3195, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28631877

RESUMO

Baidianling Capsule, which is made from 16 Chinese herbs, has been widely used for treating vitiligo clinically. In this study, the sensitive and rapid method has been developed for the analysis of chemical components in Baidianling Capsule by gas chromatography-mass spectrometry in combination with retention indices and high-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry. Firstly, a total of 110 potential volatile compounds obtained from different extraction procedures including alkanes, alkenes, alkynes, ketones, ethers, aldehydes, alcohols, phenols, organic acids, esters, furans, pyrrole, acid amides, heterocycles, and oxides were detected from Baidianling Capsule by gas chromatography-mass spectrometry, of which 75 were identified by mass spectrometry in combination with the retention index. Then, a total of 124 components were tentatively identified by high-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry. Fifteen constituents from Baidianling Capsule were accurately identified by comparing the retention times with those of reference compounds, others were identified by comparing the retention times and mass spectrometry data, as well as retrieving the reference literature. This study provides a practical strategy for rapidly screening and identifying the multiple constituents of a complex traditional Chinese medicine.


Assuntos
Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/análise , Análise de Fourier , Cromatografia Gasosa-Espectrometria de Massas , Compostos Fitoquímicos/análise , Ciclotrons
20.
J Sep Sci ; 39(22): 4325-4334, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27676180

RESUMO

Cortex Fraxini is an important traditional Chinese medicine. In this work, a rapid and reliable homogenate extraction method was applied for the fast extraction for Cortex Fraxini, and the method was optimized by response surface methodology. Ultra high performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry and gas chromatography with mass spectrometry were established for the separation and characterization of the constituents of Cortex Fraxini. Liquid chromatography separation was conducted on a C18 column (150 mm × 2.1 mm, 1.8 µm), and gas chromatography separation was performed on a capillary with a 5% phenyl-methylpolysiloxane stationary phase (30 m × 0.25 mm × 0.25 mm) by injection of silylated samples. According to the results, 33 chemical compounds were characterized by liquid chromatography with mass spectrometry, and 11 chemical compounds were characterized by gas chromatography with mass spectrometry, and coumarins were the major components characterized by both gas chromatography with mass spectrometry and liquid chromatography with mass spectrometry. The proposed homogenate extraction was an efficient and rapid method, and coumarins, phenylethanoid glycosides, iridoid glycosides, phenylpropanoids, and lignans were the main constituents of Cortex Fraxini. This work laid the foundation for further study of Cortex Fraxini and will be helpful for the rapid extraction and characterization of ingredients in other traditional Chinese medicines.


Assuntos
Medicamentos de Ervas Chinesas/análise , Extratos Vegetais/química , Aesculus , Cromatografia Líquida de Alta Pressão , Ciclotrons , Análise de Fourier , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem
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