Thematische Bibliographien / Chromatographie sfc

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Auswahl der wissenschaftlichen Literatur zum Thema „Chromatographie sfc“

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Veröffentlicht am 4. Juni 2021

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Zeitschriftenartikel zum Thema "Chromatographie sfc"

Patilaya, Popi, Dadang Irfan Husori, and Henny Sri Wahyuni. "Aktivitas Antelmintik Subfraksi dariFraksi Etanol Daun Pugun Tanoh [Picria fel-teraae (Lour.)]." Talenta Conference Series: Tropical Medicine (TM) 1, no. 3 (2018): 111–13. http://dx.doi.org/10.32734/tm.v1i3.272.

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Pugun tanoh [Picria fel-terrae (Lour.)] merupakan salah satu tumbuhan obat Indonesia yang memiliki potensi sebagai antelmintik. Ekstrak etanol daun pugun tanoh dan fraksi-fraksinya mampu membunuh cacing parasit Ascaris lumbricoides dan Ascaridia gali. Pengujian terhadap aktivitas antelmintik subfraksi dari ekstrak etanol tersebut perlu dilakukan sebagai upaya untuk memperoleh senyawa bioaktifnya. Penelitian ini bertujuan untuk mengetahui aktivitas antelmintik subfraksi dari fraksi etanol daun pugun tanoh. Penelitian dilakukan dengan memfraksinasi 20g fraksi etanol daun pugun tanoh secara kromatografi cair vakum dengan fase gerak landaian n-heksana-etil asetat dan etil asetat-metanol menggunakan fase diam silika gel 60H. Setiap 250 ml cuplikan ditampung dan ditentukan pola kromatogramnya dengan kromatografi lapis tipis menggunakan fase gerak n-heksana-etilasetat (70:30) dan fase diam silika gel GF254. Cuplikan dengan pola kromatografi yang sama dikumpulkan sebagai satu subfraksi. Setelah diuapkan, subfraksi diuji aktivitas antelmintiknya terhadap Pheretima posthuma.Hasil penelitian menunjukkan bahwa fraksi etanol daun pugun tanoh menghasilkan 4 subfraksi yaitu SF1 (0,10%), SF2 (4,00%), SF3 (4,05%), dan SF4 (73,55%). Waktu kematian P. posthuma akibat paparan SF1, SF2, SF3, dan SF4 masing-masing adalah 77,00 ± 1,00 menit; 56,33 ± 1,76 menit; 79,33 ± 1,33 menit; dan 112,33 ± 0,67 menit. Subfraksi dari fraksi etanol daun pugun tanoh memiliki aktivitas antelmintik dimana SF2 lebih kuat dibandingkan SF3, SF1, dan SF4.  Pugun tanoh [Picria fel-terrae (Lour.)] is one of the Indonesian medicinal plants which has the potential as an anthelmintic. Ethanol extract of pugun tanoh leaves and their fractions were able to destroy the parasitic worms Ascaris lumbricoides and Ascaridia. The evaluation of antelmintic activity of subfraction of ethanol extract needs to be done in an effort to obtain its bioactive compounds. This study aimed to determine the anthelmintic activity of subfraction of pugun tanoh leavesethanol fraction. The study was carried out by fractionating 20g ethanol fraction of pugun tanoh leaves by vacuum liquid chromatography with a mobile phase of n-hexane-ethyl acetate and ethyl acetate-methanol using the stationary phase of silica gel 60H.Each 250 ml aliquot was collected and the chromatogram pattern was determined by thin layer chromatography using the n-hexane-ethylacetate(70:30) asmobile phase and silica gel GF254 as stationary phase. The Aliquots with same chromatographic pattern were collected as one subfraction. After being evaporated, the subfraction was tested for its anthelmintic activity against Pheretima posthuma. The results showed that ethanol fraction of pugun tanoh leaves produced 4 subfractions namely SF1 (0.10%), SF2 (4.00%), SF3 (4.05%), and SF4 (73.55%). The time of P. posthuma's death due to exposure to SF1, SF2, SF3, and SF4 was 77.00 ± 1.00; 56.33 ± 1.76; 79.33 ± 1.33; and 112.33 ± 0.67 minutes, respectively. Subfraction of ethanol fraction of pugun tanoh leaves has anthelmintic activity in which SF2 was stronger than SF3, SF1, and SF4

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Patilaya, Popi, Dadang Irfan Husori, and Linda Marhama Daulay. "ANTHELMINTIC ACTIVITY OF SUB-FRACTIONS FROM THE N-HEXANE FRACTION OF PICRIA FEL-TERRAE LEAVES ON PHERETIMA POSTHUMA." Asian Journal of Pharmaceutical and Clinical Research 11, no. 13 (2018): 59. http://dx.doi.org/10.22159/ajpcr.2018.v11s1.26568.

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Objective: This study was to evaluate the anthelmintic activity of the subfractions (SF) from n-hexane fraction of Picria fel-terrae leaves on Pheretima posthuma.Methods: The leaves ethanolic extract of P. fel-terrae solution was mixed with water in ratio of 7:3. The mixture was fractionated with n-hexane by liquid–liquid extraction. The n-hexane fraction was then separated on silica gel by vacuum liquid chromatography with n-hexane-ethyl acetate and methanol as mobile phases. The filtrates with same chromatogram pattern were combined to produce SF of the plant leaves. The SF at the concentration of 0.1% was tested on P. posthuma to evaluate its anthelmintic activity. The anthelmintic activity was determined by observing paralysis and death times of the worms. Pyrantel 0.1% and vehicle were included as positive and negative controls, respectively.Results: The study showed that n-hexane fraction of P. fel-terrae leaves produced 4 SF, namely, SF1, SF2, SF3, and SF4. The earthworms were paralyzed at 123.00, 130.33, 78.67, 74.33, and 127.33 min when treated with SF1, SF2, SF3, SF4, and pyrantel, respectively. The SF1, SF2, SF3, SF4, and pyrantel also caused the animal death at 156.00, 166.67, 107.00, 101.67, and 140.00 min, respectively. The animal paralysis and death times by those substances were shorter than negative control effects.Conclusion: This study suggests that the SF from n-hexane fraction of P. fel-terrae leaves has anthelmintic activity on P. posthuma. The effects of SF4 are strongest when compared with SF1, SF2, SF3, and pyrantel.

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Knowles, David E., Bruce E. Richter, Michele B. Wygant, Lori Nixon, and Marion R. Andersen. "Supercritical Fluid Chromatography: A New Technique for AOAC." Journal of AOAC INTERNATIONAL 71, no. 3 (1988): 451–57. http://dx.doi.org/10.1093/jaoac/71.3.451.

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Abstract Supercritical fluid chromatography (SFC) is a chromatographic technique that, in many ways, is a hybrid of gas chromatography and liquid chromatography and offers many advantages over both. As this technique continues to grow in use, SFC will become very advantageous to the AOAC analyst.

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Cutillas, Víctor, Carmen Ferrer, and Amadeo R. Fernández-Alba. "Liquid chromatography versus supercritical fluid chromatography coupled to mass spectrometry: a comparative study of performance for multiresidue analysis of pesticides." Analytical and Bioanalytical Chemistry 413, no. 23 (2021): 5849–57. http://dx.doi.org/10.1007/s00216-021-03565-4.

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AbstractAbundant studies have been published evaluating different parameters of reverse-phase liquid chromatography (LC) and supercritical fluid chromatography (SFC), both coupled to electrospray (ESI)/mass spectrometry (MS) for pesticide residue analysis. However, there is a lack of a comprehensive comparative study that facilitates deep knowledge about the benefits of using each technique. In the present study, the same mass spectrometer was used coupled to both liquid and supercritical fluid chromatographies with a multiresidue method of 215 compounds, for the analysis of pesticide residues in food samples. Through the injection of the spiked extracts, separate experiments were conducted. A study of the optimum ion source temperature using the different chromatography modes was performed. The results were evaluated in terms of sensitivity with tomato, leek, onion, and orange as representative fruit and vegetable matrices. The compounds which reported the highest area values in each chromatography were evaluated through their substance groups and polarity values. The impact of matrix effects obtained in tomato matrix was similar for both cases; however, SFC clearly showed better results in analyzing matrices with a higher number of natural co-extracted compounds. This can be explained by the combination of two effects: (i) chromatography separation and (ii) ion source efficiency. The chromatographic elution presented different profiles of matrix components, which had diverse impact on the coelution with the analytes, being more beneficial when SFC was used in the matrices studied. The data showed that the best results obtained in SFC are also related to a higher ionization efficiency even when the ESI emitter tip was not optimized for SFC flow. In the present study a comprehensive evaluation of the benefits and drawbacks of these chromatography modes for routine pesticide residue analysis related to target compounds/commodities is provided. Graphical abstract

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Pinkston, J. David. "Advantages and Drawbacks of Popular Supercritical Fluid Chromatography / Mass Spectrometry Interfacing Approaches—A User's Perspective." European Journal of Mass Spectrometry 11, no. 2 (2005): 189–97. http://dx.doi.org/10.1255/ejms.731.

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Mobile phases in supercritical fluid chromatography (SFC) have low viscosities and high diffusion coefficients with respect to those of traditional high-performance liquid chromatography (HPLC). These properties allow higher mobile phase flow rates and/or longer columns in SFC, resulting in rapid analyses and high efficiency separations. In addition, chiral SFC is becoming especially popular. Mass spectrometry (MS) is arguably the most popular “informative” detector for chromatographic separations. Most SFC/MS is performed with atmospheric pressure ionization (API) sources. Unlike LC/MS, the interface between the SFC column and the API source must allow control of the downstream (post-column) pressure while also providing good chromatographic fidelity. Here, we compare and contrast the popular interfacing approaches. Some are simple, such as direct effluent introduction with no active back pressure regulator (BPR) in high-speed bioanalytical applications. The pressure-regulating fluid interface is more versatile and provides excellent chromatographic fidelity, but is less user friendly. The pre-BPR-split interface and an interface which provides total flow introduction with a mechanical BPR are good compromises between user friendliness and performance and have become the most popular among practitioners. Applications of SFC/MS using these various interfaces are also discussed.

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Richter, B. E., D. J. Bornhop, J. T. Swanson, J. G. Wangsgaard, and M. R. Andersen. "Gas Chromatographic Detectors in SFC." Journal of Chromatographic Science 27, no. 6 (1989): 303–8. http://dx.doi.org/10.1093/chromsci/27.6.303.

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Yang, Yiwen, Yehui Wang, Zongbi Bao, Qiwei Yang, Zhiguo Zhang та Qilong Ren. "Progress in the Enantioseparation of β-Blockers by Chromatographic Methods". Molecules 26, № 2 (2021): 468. http://dx.doi.org/10.3390/molecules26020468.

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β-adrenergic antagonists (β-blockers) with at least one chiral center are an exceedingly important class of drugs used mostly to treat cardiovascular diseases. At least 70 β-blockers have been investigated in history. However, only a few β-blockers, e.g., timolol, are clinically marketed as an optically pure enantiomer. Therefore, the separation of racemates of β-blockers is essential both in the laboratory and industry. Many approaches have been explored to obtain the single enantiomeric β-blocker, including high performance liquid chromatography, supercritical fluid chromatography and simulated moving bed chromatography. In this article, a review is presented on different chromatographic methods applied for the enantioseparation of β-blockers, covering high performance liquid chromatography (HPLC), supercritical fluid chromatography (SFC) and simulated moving bed chromatography (SMB).

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Al Bakain, Ramia Z., Yahya Al-Degs, Bertyl Andri, Didier Thiébaut, Jérôme Vial, and Isabelle Rivals. "Supercritical Fluid Chromatography of Drugs: Parallel Factor Analysis for Column Testing in a Wide Range of Operational Conditions." Journal of Analytical Methods in Chemistry 2017 (2017): 1–13. http://dx.doi.org/10.1155/2017/5340601.

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Retention mechanisms involved in supercritical fluid chromatography (SFC) are influenced by interdependent parameters (temperature, pressure, chemistry of the mobile phase, and nature of the stationary phase), a complexity which makes the selection of a proper stationary phase for a given separation a challenging step. For the first time in SFC studies, Parallel Factor Analysis (PARAFAC) was employed to evaluate the chromatographic behavior of eight different stationary phases in a wide range of chromatographic conditions (temperature, pressure, and gradient elution composition). Design of Experiment was used to optimize experiments involving 14 pharmaceutical compounds present in biological and/or environmental samples and with dissimilar physicochemical properties. The results showed the superiority of PARAFAC for the analysis of the three-way (column × drug × condition) data array over unfolding the multiway array to matrices and performing several classical principal component analyses. Thanks to the PARAFAC components, similarity in columns’ function, chromatographic trend of drugs, and correlation between separation conditions could be simply depicted: columns were grouped according to their H-bonding forces, while gradient composition was dominating for condition classification. Also, the number of drugs could be efficiently reduced for columns classification as some of them exhibited a similar behavior, as shown by hierarchical clustering based on PARAFAC components.

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Li, Jian Jun, and Kevin B. Thurbide. "Novel pressure control in supercritical fluid chromatography using a resistively heated restrictor." Canadian Journal of Chemistry 87, no. 3 (2009): 490–95. http://dx.doi.org/10.1139/v09-005.

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An alternative means of independently controlling column pressure in supercritical fluid chromatography (SFC) by resistively heating the post-column restrictor is demonstrated. Compared to conventional block heating methods, resistive restrictor heating provides at least four times greater pressure programming rates and allows for much faster cooling times in between runs, thereby increasing sample throughput. When applying resistive restrictor heating in proximity to a flame ionization detector, the chromatographic baseline noise increases substantially and obscures peaks. However, adding about 100 mL/min of nitrogen into the flame burner essentially removes this noise and returns the detector response to normal. The analyte retention time in consecutive pressure gradient trials reproduces well with a minimal relative standard deviation of 0.36% (n = 3). The resistive restrictor heating technique presented is also found to be equally effective for either capillary or packed SFC operating modes. Results suggest that this method can potentially provide a simple, inexpensive, and convenient alternative to limited passive restrictors or more costly and complex backpressure regulators that are often used to maintain system pressure in supercritical fluid chromatography.

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Bajpai, Vivek K., Rajib Majumder, and Jae Gyu Park. "Isolation and purification of plant secondary metabolites using column-chromatographic technique." Bangladesh Journal of Pharmacology 11, no. 4 (2016): 844. http://dx.doi.org/10.3329/bjp.v11i4.28185.

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Chromatographic techniques have significant role in natural products chemistry as well as contribute dramatically in the discovery of novel and innovative compounds of pharmaceutical and biomedical importance. This study focused on step-by-step visual demonstration of fractionation and isolation of biologically active plant secondary metabolites using column-chromatographic techniques. Isolation of bioactive compounds using column-chromatographic involves: a) Preparation of sample; b) Packing of column; c) Pouring of sample into the column; d) Elution of fractions; and e) Analysis of each fractions using thin layer chromatography. However, depending on nature of research, compounds can be further purified using high performance liquid chromatography (HPLC), and nuclear magnetic resonance (NMR) spectral analyses.Video Clips<a href="https://www.youtube.com/v/pr8mrBoI8xA">Part 1:</a> 3 min 45 sec<a href="https://www.youtube.com/v/rYrfClKn-og">Part 2:</a> 6 min 21 sec<a href="https://www.youtube.com/v/kffHXxuPwbo">Part 3</a>: 4 min 45 sec

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Dissertationen zum Thema "Chromatographie sfc"

Martial, Frédérique. "Détection et évolution des additifs du polypropylène à l'aide de la SFC et du couplage SFE/SFC : influence sur les propriétés physiques du polypropylène." Rouen, 1995. http://www.theses.fr/1995ROUES050.

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Le polypropylène (PP) est un matériau polyvalent de plus en plus utilisé. Pour éviter qu'il se dégrade rapidement, on lui ajoute des additifs de stabilisation. Au cours du temps, ils sont consommés et on observe parallèlement le vieillissement du PP qui se caractérise par une évolution de ses propriétés. L'objectif de nos travaux était de relier la disparition des additifs avec l'évolution des propriétés mécaniques du PP vieilli, dans le but de prévoir son temps de vie en fonction de sa stabilisation et d'appliquer ces résultats au problème du recyclage. Nous avons dans un premier temps optimisé une méthode d'extraction et d'analyse des additifs en utilisant le couplage SFE/SFC (extraction par fluide supercritique/chromatographie par fluide supercritique). L'étude de l'influence des différents paramètres nous a permis de mettre au point une technique de caractérisation fiable et reproductible et d'obtenir des rendements d'extraction appréciables. Nous avons dans un deuxième temps appliqué cette technique à l'évolution d'un antioxydant contenu dans le polypropylène. Nous avons d'une part étudié la disparition de l'additif par couplage SFE/SFC, et d'autre part suivi les propriétés mécaniques du PP au cours de son vieillissement thermique. Des corrélations entre allongement et contrainte à la rupture avec la concentration en additif ont été établies et peuvent être utilisées dans le cadre du recyclage du PP. Les différents résultats obtenus nous ont donc permis d'atteindre notre objectif pour l'antioxydant étudié

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Raimbault, Adrien. "Analyse de molécules d'intérêt biologique en chromatographie supercritique et chromatographie unifiée - Etudes fondamentales et applications." Thesis, Orléans, 2019. http://www.theses.fr/2019ORLE3021.

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La SFC est une technique analytique ancienne qui a mis du temps à s’implanter dans les mœurs des chromatographistes, restant de longues années dans l’ombre de l’HPLC et la GC. Les petites molécules peu polaires s’analysent facilement grâce à cette technique du fait de la faible polarité du dioxyde de carbone. Qu’en est-il des composés polaires ? Plusieurs méthodes ont été mises en place afin de les analyser. Une technique intermédiaire entre la SFC et l’HPLC a été utilisée, la chromatographie unifiée.Ce travail de recherche traite de méthodes pour analyser des molécules de polarité plus élevée, tels que des acides aminés. Des phases stationnaires ont été étudiées grâce au modèle LSER pour comprendre le comportement de telles molécules dans un milieu supercritique. Un développement de méthode a été effectué pour l’analyse d’acides aminés. Cette méthode a ensuite été utilisée pour diverses applications (compléments alimentaires, plante d'intérêt pharmaceutique) SFC is an old analytical technique that took time to establish itself in the morals of chromatographers, remaining for many years in the shadow of HPLC and GC. Small and non-polar molecules are easily analysed using this technique because of the low polarity of carbon dioxide. What about polar compounds? Several methods can be used to analyse them. An intermediate technique between SFC and HPLC was used, unified chromatography.This research deals with methods for analysing molecules of higher polarity, such as amino acids. Stationary phases were studied using the LSER model to understand the behaviour of such molecules in a supercritical environment. A method development was performed for amino acid analysis. This method was then used for various applications (food supplements, plant of pharmaceutical interest)

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West, Caroline. "Caractérisation et utilisation du carbone graphite poreux et autres phases aromatiques en chromatographie subcritique." Paris 11, 2005. http://www.theses.fr/2005PA112377.

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Iguiniz, Marion. "Développement de méthodes bidimensionnelles en ligne LCxLC-UV/MS et LCxSFC-UV pour l’analyse de composés pharmaceutiques." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1200/document.

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La chromatographie en phase liquide bidimensionnelle est une technique à fort potentiel, offrant un grand pouvoir de séparation. Après avoir démontré son intérêt dans l’industrie pharmaceutique et présenté les enjeux liés à l’analyse quantitative, une attention particulière est portée sur le développement de méthodes. Dans l’idée de développer une stratégie d’analyse générique, la première étape est de sélectionner un set de trois systèmes 2D par le biais d’une approche développée au laboratoire. La deuxième étape est d’évaluer le potentiel de ces systèmes pour l’analyse quantitative. Ces deux étapes ont conduit à la proposition d’une stratégie d’analyse applicable à l’analyse pharmaceutique dans un contexte industriel. Enfin le potentiel du couplage RPLCxSFC est envisagé dans deux cas de figure différents. Premièrement, dans le but de comparer ce couplage aux séparations RPLCxRPLC développées dans le cadre d’une stratégie analytique générique, en termes de pouvoir de séparation. Deuxièmement, dans le cadre de l’analyse de composés chiraux, en développant un couplage sRPLCxSFC permettant une analyse achirale/chirale simultanée. Les avantages d’une telle approche ont été mis en avant en la comparant aux approches conventionnelles Two-dimensional liquid chromatography (2D-LC) is a powerful technique considering its high separation power. After showing the advantage of 2D-LC in the pharmaceutical area and presenting the challenges related to quantitative analysis, special attention was paid to method development. With the aim of developing a generic analytical strategy for pharmaceuticals, the first step of our approach consisted in selecting a set of three 2D-systems with the help of a methodology previously developed. In a second step, the potential of these 2D-systems was evaluated for the purpose of quantitative analysis. An analytical strategy able to be applied to pharmaceutical analysis in an industrial context was proposed. Finally, the potential of RPLCxSFC was investigated in two different cases. Firstly, for comparing this on-line two dimensional technique to on-line RPLCxRPLC with respect of the separation power. Secondly, for chiral compounds by developing a selective RPLCxSFC method for simultaneous achiral-chiral analysis. The advantage of such method was highlighted by comparing to conventional approaches

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Mourier, Pierre. "La Chromatographie en phase supercritique avec le dioxyde de carbone." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37599852p.

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Adam, Frédérick Marie. "Recherche de sélectivité pour l'analyse moléculaire des distillats moyens par chromatographie multidimensionnelle." Paris 6, 2008. http://www.theses.fr/2008PA066266.

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Dans le cadre de l’amélioration de l’outil de raffinage, l’analyse moléculaire est essentielle pour la conception de modèles cinétiques utilisés pour l’optimisation des unités de production. Les techniques conventionnelles d’analyse ne permettant pas de répondre à ce challenge, la chromatographie en phase gazeuse bidimensionnelle (GC-2D) a été mise en œuvre. Le premier volet de l'étude concerne la spéciation de composés oxygénés dans les coupes gazoles. Le pouvoir résolutif de la GC-2D a été utilisé pour séparer les esters d’huiles végétales des hydrocarbures auxquels ils sont mélangés. Le développement des moyens de détection et des conditions de séparation en GC-2D a quant à lui aboutit à une séparation inédite des dérivés azotés présents dans les gazoles. Pour la séparation des hydrocarbures, le développement méthodologique des conditions de séparation ainsi que le couplage d’un vecteur de séparation, la chromatographie en phase liquide en amont de la GC-2D ont été étudiés. Cette seconde approche ayant donné de bons résultats, un ensemble analytique totalement automatisé permettant l’analyse PIONA étendue des distillats moyens a été réalisé.

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Delbeke, Valérie. "Chromatographie en phase supercritique (CPS) et détection d'émission atomique (AED) appliquées à l'analyse de produits pétroliers : perspectives du couplage CPS-AED." Rouen, 1995. http://www.theses.fr/1995ROUE5022.

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La première partie de ce travail concerne l'application de la chromatographie en phase supercritique à l'analyse de produits pétroliers, notamment pour réaliser une méthode de distillation simulée. Des solutions aux difficultés rencontrées sont proposées. Dans la seconde partie, on réalise l'étude et la mise au point de la détection d'émission atomique couplée à la chromatographie en phase gazeuse. Cette technique est appliquée à l'analyse qualitative de nombreux produits pétroliers. L'analyse quantitative révèle quant à elle la nécessité d'améliorer le contrôle des différents débits des gaz utilisés. La perspective du couplage de ces deux techniques est ensuite envisagée et débattue

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Lemasson, Elise. "Stratégies chromatographiques en phase liquide et supercritique pour l'analyse de candidats médicaments." Thesis, Orléans, 2018. http://www.theses.fr/2018ORLE2005/document.

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Le profilage d’impuretés de candidats médicaments est une préoccupation majeure des industries pharmaceutiques. L’identification et la quantification des impuretés doivent être strictement contrôlées pour assurer l’efficacité et la toxicité limitée du principe actif. Il est donc nécessaire de disposer de méthodes analytiques performantes afin de s’assurer que l’ensemble des impuretés est identifié. L’HPLC phase inverse sur phase C18 reste aujourd’hui la méthode de choix pour cette tâche. Cependant, il arrive que cette méthode échoue, notamment lorsque le principe actif n’est pas suffisamment retenu sur la colonne ou que les impuretés ne sont pas parfaitement séparées du composé principal. Il est alors essentiel de pouvoir se tourner vers des méthodes analytiques alternatives et complémentaires.Ce travail de recherche traite du développement et de l’évaluation de méthodes analytiques alternatives à l’HPLC phase inverse sur phase C18 pour le profilage d’impuretés de principes actifs pharmaceutiques. L’HPLC phase inverse sur d’autres phases stationnaires, l’HPLC mixed-mode ainsi que la SFC ont été explorées et leurs performances chromatographiques comparées. La comparaison et l’étude des différentes méthodes ont permis de proposer une stratégie d’analyse du candidat médicament Impurity profiling of drug candidates is a significant concern of pharmaceutical industries. The identification and quantification of impurities must be strictly controlled to ensure the efficacy and limited toxicity of the active ingredient. It is therefore necessary to have efficient analytical methods to ensure that all impurities are identified. Today, reversed-phase HPLC with C18 column remains the method of choice for this task. However, this method sometimes fails, particularly when the active pharmaceutical ingredient is not sufficiently retained on the column or when the impurities are not resolved from the main compound. It is therefore essential to turn to alternative and complementary analytical methods.This work deals with the development and evaluation of alternative analytical methods to reversed-phase HPLC on C18 phase for impurity profiling of pharmaceuticals. Reversed-phase HPLC on other stationary phases, mixed-mode HPLC as well as SFC were explored and their chromatographic performances compared. The comparison and the study of the different methods allowed proposing a strategy of analysis of the drug candidate

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COUSIN, JACKY. "Couplage entre la chromatographie en phase supercritique et la spectrometrie de masse." Paris 6, 1987. http://www.theses.fr/1987PA066776.

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Conception et realisation d'un couplage entre un chromatographe en phase supercritique avec des colonnes capillaires et un spectrometre de masse, en mode d'ionisation chimique. L'appareil cps-sm a ete monte et a ete ensuite applique a l'analyse de substances peu volatiles ou thermosensibles, telles que des hydrocarbures polyaromatiques, des esters d'acides gras, des triglycerides et des peg. Comparaison avec le couplage chromatographie en phase liquide spectrometrie de masse

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Chouchi, Dalida. "Extrographie : couplage in situ entre extraction et chromatographie supercritique, application à la déterpénation et à la détoxification des huiles essentielles d'agrumes." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL022N.

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L’utilisation du dioxyde de carbone supercritique comme éluant d'extraction pour les produits naturels a fait ses preuves depuis quelques années, toutefois, il reste peu sélectif pour le fractionnement de produits de structure chimique proche. Pour la séparation de ce type de composés, les procédés chromatographiques supercritiques, au contraire, donnent de bons résultats, cependant ceux-ci sont peu productifs par rapport à l'extraction supercritique. Dans ce travail, nous présentons les recherches sur le développement d'un nouveau procédé de fractionnement baptisé extrographie qui est le couplage in situ entre extraction et chromatographie supercritique. Ce procédé est utilisé pour la séparation de produits modèles: le limonène (un terpène) et le citral (un terpène oxygéné). Dans la première partie de ce mémoire, nous proposons un modèle qui permet de mieux comprendre les phénomènes impliqués lors du processus extrographique, de prévoir le comportement du système CO2-limonène-citral sous certaines contraintes, et qui permettra d'ajuster en conséquence les paramètres de la séparation limonène-citral en présence de CO2. Dans la seconde partie, nous présentons les résultats de l'utilisation de ce procédé de fractionnement, dans le but de réduire la teneur en terpènes et d'extraire les composés toxiques présents dans les huiles essentielles d'agrumes. Le fractionnement suivi par GC et GC-MS, nous a permis de contrôler d'une manière plus précise les paramètres nécessaires à l'optimisation de la déterpénation et de la détoxification de ces huiles

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Bücher zum Thema "Chromatographie sfc"

Berger, T. A. Packed column SFC. The Royal Society of Chemistry, 1995.

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Workshop, on Supercritical Fluid Chromatography (1988 Park City Utah). SFC applications: The 1988 Workshop on Supercritical Fluid Chromatography, held in Park City, Utah, on January 12-14, 1988. Brigham Young University Press, 1988.

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Symposium/workshop on Supercritical Fluid Chromatography (1989 Snow Bird, Utah). SFC applications: The 1989 Symposium/workshop on Supercritical Fluid Chromatography held at Snow Bird, Utah, on June 13-15, 1989. Brigham Young University Press, 1989.

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Lubcke, K. Supercritical-fluid chromatography: Commissioning and evaluation of a Gilson SF3 for the fractioncollection of lubricant additives. University of Wolverhampton, 1993.

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Muneo, Saito, Yamauchi Yoshio, and Okuyama Tsuneo, eds. Fractionation by packed-column SFC and SFE: Principles and applications. VCH, 1994.

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BERGER, T. PACKED COLUMN SFC (Chromatography Monographs). Royal Society of Chemistry, 1995.

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Associates, White, ed. SFaCts: A comprehensive bibliography of SFC and related articles. The Associates, 1987.

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Chromatography of polymers: Characterization by SEC and FFF. American Chemical Society, 1993.

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Provder, Theodore. Chromatography of Polymers: Characterization by SEC and FFF (Acs Symposium Series). An American Chemical Society Publication, 1998.

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1939-, Provder Theodore, and American Chemical Society Meeting, eds. Chromatography of polymers: Hyphenated and multidimensional techniques. American Chemical Society, 1999.

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Buchteile zum Thema "Chromatographie sfc"

Klesper, E., and S. Küppers. "Chromatographie mit überkritischen dichten mobilen Phasen (SFC)." In Analytiker-Taschenbuch. Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-77526-0_2.

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Gey, Manfred H. "Chromatographie-3: LC/HPTLC & GC – SFC." In Instrumentelle Analytik und Bioanalytik. Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-63952-8_6.

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Wenclawiak, Bernd. "SFC and SFE: An Introduction for Novices." In Analysis with Supercritical Fluids: Extraction and Chromatography. Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-77474-4_1.

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Klesper, Ernst, and Franz P. Schmitz. "Gradients in SFC." In Analysis with Supercritical Fluids: Extraction and Chromatography. Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-77474-4_5.

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Greibrokk, Tyge. "Injection Techniques in SFC." In Analysis with Supercritical Fluids: Extraction and Chromatography. Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-77474-4_6.

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Brunner, Gerd. "Chromatography with Supercritical Fluids (Supercritical Fluid Chromatography, SFC)." In Topics in Physical Chemistry. Steinkopff, 1994. http://dx.doi.org/10.1007/978-3-662-07380-3_9.

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McElroy, Con R., and Thomas M. Attard. "CHAPTER 5. Supercritical Fluid Chromatography (SFC)." In Green Chemistry Series. Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/9781788013543-00106.

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Mori, Sadao, and Howard G. Barth. "SEC Method Development." In Size Exclusion Chromatography. Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/978-3-662-03910-6_5.

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Brunner, Gerd H., and Dirk Upnmoor. "Scale up of Supercritical Fluid Chromatography (SFC)." In Supercritical Fluids. Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-015-8295-7_28.

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Arpino, P. J. "Combined Supercritical Fluid Chromatography/Mass Spectrometry (SFC/MS)." In Mass Spectrometry in the Biological Sciences: A Tutorial. Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2618-2_15.

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Konferenzberichte zum Thema "Chromatographie sfc"

Bonanno, Anthony S., Kelly L. Norton, Jyisy Yang, and Peter R. Griffiths. "On-line detection for capillary and packed-column supercritical fluid chromatography by direct-deposition SFC-FTIR." In Luebeck - DL tentative, edited by Herbert M. Heise, Ernst H. Korte, and Heinz W. Siesler. SPIE, 1992. http://dx.doi.org/10.1117/12.56410.

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Strachan, S., E. Kontopoulou, D. Reinhardt, B. Giebel, and B. Thakur. "Comparison of differential ultracentrifugation (DC) and size exclusion chromatography (SEC) based exosome isolation methods." In 31. Jahrestagung der Kind-Philipp-Stiftung für pädiatrisch onkologische Forschung. Georg Thieme Verlag KG, 2018. http://dx.doi.org/10.1055/s-0038-1645025.

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Ramesh, Chetan, Abhinav Bhushan, Edward Overton, and Michael C. Murphy. "Design and Fabrication of Fast Micro Heaters for Temperature Programming Micro Gas Chromatographs." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-43112.

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Prototype, low power, high rate resistance heaters for temperature programming metal micro gas chromatograph (GC) separation column chips were fabricated using UV lithography. Spin coated polyimide was used as the electrically insulating layer between the heating coil and the GC column chip because of its excellent thermal properties — in particular the ability to match the coefficient of thermal expansion with nickel and copper, and ease of application. Low resistivity, copper and nickel, metal heating elements were electrodeposited directly on the polyimide layer spin coated on top of the nickel GC column chips. In experiments, the microfabricated heaters were able to heat the GC column at rates from 5°C/sec to 50°C/sec under PID control. Temperatures from 125°C to 250°C were maintained for soak times of up to 30 seconds. The heaters can be used to generate a variety of temperature programming profiles and offer flexibility in selecting the different ramp rates and soak temperatures needed for different applications.

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Qiu, Ni, Gangwen Xie, Qiang Yao, Yulong Miao, Fuping Zeng, and Liangjun Dai. "The Detection of Hydrolyzable Fluoride in SF6 Equipment by Ion Chromatography and Application in Fault Determination." In 2019 2nd International Conference on Electrical Materials and Power Equipment (ICEMPE). IEEE, 2019. http://dx.doi.org/10.1109/icempe.2019.8727271.

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Stachowiak, Jeanne C., Erin E. Shugard, Pamela Caton, et al. "Automated Sample Preparation System for Rapid Biological Threat Detection." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-80945.

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Rapid, automated sample preparation of bacterial cells and spores is required for threat analysis by remotely deployed chemical and biological warning systems. Sandia is designing, building, and testing an automated front-end sample preparation system based on miniature and microfluidic components, with the goal of concentrating bacterial species collected from the air, harvesting and solubilizing proteins from them, and delivering them to Sandia’s MicroChemLab capillary gel electrophoresis system1,2 for analysis (Fig. 1). Miniature, motorized valves and pumps control flow between system components connected by fused silica capillaries (Fig. 4). Sample processing modules include concentration by dielectrophoresis in an array of insulating posts or by mechanical filtration; heat-activated chemical lysis; mechanical filtration; removal of chemical lysis agents by size exclusion chromatography (SEC); and in-capillary fluorescent labeling.

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Owen, B. A., and W. G. Owen. "ASSOCIATION OF HEPARIN AND FACTOR Xa: INFLUENCE ON THE RATE OF INHIBITION OF FACTOR Xa BY ANTITHROMBIN III-HEPARIN." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643837.

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Association of heparin non-covalently with bovine factor Xa was analyzed by Superose-12 gel chromatography. In 0.05 M NaCl, 0.02 M Tris, pH 7.5, DEGR-Xa (factor Xa inactivated by dans-Glu-Gly-Arg-CH2Cl) was eluted as a single, sharp peak at Ve/Vt=0-65 (elution volume/internal volume). Mixtures of heparin and DEGR-Xa were eluted as two partially resolved peaks of protein at Ve/Vt=0.59 and 0.65. The fraction of DEGFUXa in the leading peak was directly proportional to [heparin], and at 100 yM heparin the leading peak contained more than half the total protein. When 0.02 M HEPES was substituted for Tris a single, slightly broadened peak at Ve/Vt=0.64 was obtained on chromatography of 100 μM heparin and 10 μM DEGR-Xa. In a buffer system comprising 0.02 M Tris, 0.02 M HEPES, 0.03 M NaCl, pH 7.5, two peaks were eluted at Ve/Vt=0.59 and 0.65. Therefore, Tris increases the affinity of DEGR-Xa for heparin.Solutions buffered with Tris or HEPES were compared for effects on the kinetics of inhibition of factor Xa by antithrombin III-heparin. Reaction mixtures containing 1 nM factor Xa, 30 nM heparin and 600 nM antithrombin III were assayed with S-2222 at intervals of 2-10 sec. Reagent concentrations were chosen (a) to assure pseudo-first-order kinetics, (b) to have [heparin]<< Kq for factor Xa-heparin, and (c) to bind virtually all available heparin to antithrombin III. The same second-order rate constant, Kobs=2.5×107 M−1s−1, was obtained in both buffer systems. We conclude that the association of factor Xa with heparin observed directly by gel chromatography does not contribute to the reaction rate of factor Xa with antithrombin III-heparin.

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Orthner, Carolyn L., Prabir Bhattacharya, and Dudley K. Strikland. "PURIFICATION AND CHARACTERIZATION OF A PROTEIN C ACTIVATOR FROM THE VENOM OF AGKISTRODON CONTORTRIX CONTORTRIX." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643813.

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There are two recent reports on the purification and properties of a protein C activator (PCA) from the venom of the Southern copperhead snalce. The purification of a 37,000 Mr nonenzymatic PCA (Martinoli and Stocker, Thrcmb. Res. 43, 253, 1976) as well as of a 20,000 Mr thrombin-like enzyme (Klein and Walker, Biochem. ,25, 4175, 1986) have been described. The purpose of this investigation was to purify and further characterize the PCA(s) from this vencm. A PCA has been isolated by sulphopropyl-Sephadex followed by gel filtration chromatography resulting in approximately a 100-fold purification with a 50% yield. PCA appeared as a single band on SDS-PAGE with an estimated Mr of 32,000 or 37,000 in the absence or presence of β-mercaptoethanol, respectively. High pressure gel permeation cinematography of PCA in Tris-buffered saline, pH 7.5 resulted in a single protein peak with a Mr of 39,000 which was coincident with activity. PCA was a potent activator of human protein C (PC) with a Km for PC of 0.6uM and a Vm of 0.02 sec-1. In addition, PCA catalyzed the arnidolysis of Tosyl-gly-pro-arg-p-nitroanilide (TGPRpNA) with a Km of 1.1 irM and a Vim of 66 sec-1. The rate of arnidolysis of five other pept idyl-arginyl-pNA substrates each tested at 1.0 mM was < 10% that of TGPRpNA. PCA was inhibited by nitrophenylguanidi-nobenzoate (NPGB), phenylmethylsulphonylflouride, D-phe-pro-arg-chloromethyi_ketone (PPACK) and soybean trypsin inhibitor indicating that PCA is a serine protease. The active site concentration of PCA as measured by NPGB titration was 90% that of the protein concentration. Measurement of the rate of PCA inhibition at varying levels of PPACK indicated that it had a Ki of 34uM .and an aUcylation rate constant of 0.09 min-1. PCA activation of PC was completely inhibited by CaC12 with an apparent Ki of 99uM. Since neither PCA arnidolysis of TGPRpNA nor inhibition by PPACK was affected by Ca2+, the effect of this metal was likely on the substrate PC. In summary, a PCA has been purified to homogeneity and has properties which are distinct from those reported. PCA premises to be a useful enzyme in studies of PC and its activation.

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Palareti, G., M. Maccaferri, M. Poggi, et al. "EFFECTS OF GABEXATE MESILATE (FOY), A NEW SYNTHETIC SERINE PROTEASE INHIBITOR, ON BLOOD COAGULATION IN PATIENTS WITH DIC." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644343.

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A pilot open controlled study of FOY was performed in 20 intensive care patients (pts, age 18-63) with DIC diagnosed with standard laboratory criteria (at least 3 of the following: Normotest 70%, fibrinogen 150 mg%, AT III 80%, FDP 20 ug/ml, platelets 150000). Besides the usual treatments, FOY was given to 10 pts (FOY G.) by continuous i.v. infusion (1mg/kg/h) for up to 7 days, while in 10 control pts (Hep.G.) the treatment included low dose s.c. heparin. Blood clotting tests were performed at admission to the study and daily for 7 days; we consider here results obtained at baseline and at the 4th (7 survivors in FOY G. and 10 in Hep.G.) and the 7th day (6 surv. in FOY G. and 9 in Hep. G.). Statistical evaluation was made by means of the twotailed Wilcoxon test for non parametric paired data. In the FOY G. depressed baseline AT III and plasminogen (Plgn) activities (61.8+/-5.3% and 57+/-5.5% respectively) significantly increased at 4th day (92+/-11.2% and 83+/-3.1% p<0.05), Plgn furtherly significantly increased at 7th d. (p<0.05). In the Hep.G. Normotest, Plgn and Platelets significantly (p<0.05) increased at 4th day, but no changes in AT III were found. Fibrinogen increased in both groups during the observation period (pA0.05). Serum and especially "plasma" FDP (specific monoclonal Ab to fgn and fibrin degradation products), as well as D-Dirner and HMW fgn complexes measured by exclusion chromatography, decreased especially in the FOY G. These results show that FOY modifies the clotting laboratory pattern in DIC pts, likely by an antithrombin effect. The clinical significance of these effects remains, however, to be explored.

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Winocour, P. P., P. D. Rand, J. D. Vickers, R. L. Kinlough-Rathbone, and J. F. Mustard. "ENHANCED THROMBIN-INDUCED AGGREGATION AND INOSITOL TRISPHOSPHATE FORMATION OF PLATELETS FROM SPONTANEOUSLY HYPERCHOLESTEROLEMIC RATS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643811.

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Platelets from rats with diet-induced hypercholesterolemia are hypersensitive to thrombin through a pathway independent of released ADP or thromboxane A2 (TXA2) formation. We examined if platelets from rats with spontaneous hypercholesterolemia (HC) are similarly hypersensitive. HC rats (plasma cholesterol: 130±4 mg/dl, n=15) were compared with their normocholesterolemic genetic controls (NC) (87±4 mg/dl, p<0.001, n=16). Total cholesterol/109 platelets was not different between the groups (HC: 0.314±0.032 μmole, n=7; NC: 0.357±0.046 ymole, n=7). Washed platelets were prelabelled with 14c-serotonin. In the presence of aspirin (to inhibit TXA2 formation) and creatine phosphate/creatine phosphokinase (CP/CPK) (to remove released ADP), HC platelets aggregated more (22±2%, n=ll) than NC platelets (10±4%, n=12, p<0.01) in response to thrombin (0.065 U/ml); 14C release was not different. Thrombin causes inositol mono-, bis-, and trisphosphate (IP, IP2, IP3) formation from phosphoinositides (PI, PIP, PIP2 respectively) in rabbit platelets; IP3 may be involved in Ca++ mobilization and the release of granule contents. We examined if enhanced inositol phosphate formation was associated with hypersensitivity of HC platelets. Platelets were prelabelled with 3H-inositol and stimulated with thrombin (0.057 U/ml) for 30 sec in the presence of aspirin and CP/CPK. Li+ (20 mM) was used to prevent degradation of inositol phosphates to inositol. 3H-IP, IP2 and IP3 were isolated by ion-exchange chromatography. The increase in radioactivity (dpm/109 platelets) in IP2 and IP3 following thrombin stimulation was greater in HC platelets (IP2: 2210±160, n=4; IP3: 1430±180, n=4) than in NC platelets (IP2: 660±150, n=4, p<0.001; IP3: 490±100, n=4, p<0.01); IP was not different.Thus platelets from spontaneously HC rats are hypersensitive to thrombin independently of released ADP or TXA2 formation. This hypersensitivity is associated with only moderate increases in plasma cholesterol and no detectable increase in total platelet cholesterol. Enhanced labelling of IP3 may indicate that enhanced activity of the pathways leading to IP3 formation is associated with this hypersensitivity.

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