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Antidepresantų amitriptilino ir venlafaksino mišinio išskyrimo iš kraujo plazmos optimalių sąlygų nustatymas / The determination of optimal conditions of isolation antidepressant amitriptyline and venlafaxine mixture from human plasmaGuokaitė, Gabrielė 18 June 2014 (has links)
Atlikta mokslinių literatūros šaltinių apžvalga. Tiriamųjų medžiagų identifikavimui ir kiekybinei analizei pritaikyta ir validuota efektyvioji skysčių chromatografija. Antidepresantų mišinys išskirtas iš kraujo plazmos kietos fazės ekstrakcijos metodu. KFE metodas optimizuotas keičiant eliuentą ir eliuento pH. Atliktas optimizacijos sąlygų palyginimas. Nustatyti 3 organiniai tirpikliai, kuriais efektyviausiai eliuuojamos sorbente sulaikytos tiriamosios medžiagos bei gauti statistiškai patikimi rezultatai (p>0,05) : 2 proc. etano rūgšties tirpalas 100 proc. metanolyje, 2 proc. etano rūgšties tirpalas 80 proc. metanolyje ir 2 proc. metano rūgšties tirpalas 100 proc. metanolyje. / In this thesis was performed research of scientific literature. Applied and validated high performance liquid chromatography for identification and quantification of target compounds. Antidepressant mixture extracted from blood plasma samples using LLE and SPE methods. SPE method was optimized by changing the elutor and its pH. Three organic solvents were determined, which best elute target compounds from sorbent and show statistical confidence (p>0,05): 2 proc. acetic acid in 100 proc. methanol solution, 2 proc. acetic acid in 80 proc. methanol solution and 2 proc. formic acid in 100 proc. methanol solution.
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Vaistinio augalo Leonurus cardiaca L. eterinių aliejų, fenolinių junginių ir antioksidacinio aktyvumo vertinimas / Evaluation of essential oils, phenolic compounds and antioxidant activity in medicinal plant Leonurus cardiaca LMeškauskaitė, Dovilė 18 June 2014 (has links)
Šio darbo tiriamasis objektas paprastoji sukatžolė (Leonurus cardiaca L.) – notrelinių (Lamiaceae) šeimos daugiametis, fenolinius junginius, eterinį aliejų, alkaloidus kaupiantis augalas. Leonurus cardiaca L. pasižymi antiaritminiu, kraujo spaudimą mažinančiu, raminančiu, uždegimą mažinančiu, antibakteriniu poveikiu.
Darbo tikslas – nustatyti eterinio aliejaus komponentus, fenolinių junginių kiekį bei antioksidacinį aktyvumą augalinėje paprastųjų sukatžolių (Leonurus cardiaca L.) antžeminės dalies žaliavoje, surinktoje skirtingose augavietėse bei palyginti šių junginių pasiskirstymą lapuose, stiebuose ir žolėje. Uždaviniai – identifikuoti Leonurus cardiaca L. eterinio aliejaus komponentus dujų chromatografijos–masių spektrometrijos metodu; nustatyti bendrą fenolinių junginių kiekį, bendrą flavonoidų kiekį bei antioksidacinį aktyvumą spektrofotometriniu metodu ir palyginti šių junginių pasiskirstymą skirtinguose augalo organuose bei bandiniuose, rinktuose skirtingose augavietėse; įvertinti atskirų fenolinių rūgščių ir flavonoidų įtaką bendram ekstraktų antioksidaciniam aktyvumui, panaudojant efektyviosios skysčių chromatografijos su pokolonėline DPPH reakcijos detekcija metodą.
Germakrenas D, α-humulenas, β-kariofilenas, trans-verbenolis, β-kubebenas, limonenas – pagrindiniai Leonurus cardiaca L. eterinio aliejaus komponentai, jų kiekis pagal bendrą smailių plotą skirtinguose regionuose rinktoje žaliavoje svyruoja nuo 27,8 x106 iki 11,8 x106. Tiek lapuose, tiek žolėje... [toliau žr. visą tekstą] / Motherwort (Leonurus cardiaca L.) is a perennial medicinal plant of Labiatae (Lamiaceae) family. It accumulates many biologically active substances (phenolic compounds, flavonoids, essential oil, alkaloids). Leonurus cardiaca L. is a perspective herb of its antiarrhythmic, hypotensive, sedative, antiinflammatory, antibacterial and antioxidative effect.
The aim of this study – to identify components of essential oil, content of phenolic compounds and antioxidant activity in motherwort (Leonurus cardiaca L.) raw material, collected from the different places of Lithuania and to compare their distribution in leaves, stems and grass. Tasks – to identify Leonurus cardiaca L. components of essential oil by gas chromatography–mass spectrometry; to determine the total phenolic compounds, total flavonoid content and DPPH radical scavenging activity by spectrophotometry and to compare the distribution of these active compounds in different organs of the plant and sample, collected from the different places of Lithuania; to assess the individual phenolic acids and flavonoids impact on the antioxidant activity of extracts, using postcolumn high performance liquid chromatography (HPLC)-DPPH method.
Germacrene D, α-humulene, β-caryophyllene, trans-verbenol, β-cubebene, limonene are the major essential oil components of Leonurus cardiaca L., their content by the total area of the peaks in the different samples of the raw material were determined from 27,8 x 106 to 11,8 x 106. The leaves... [to full text]
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Adsorption Isotherm Parameter Estimation in Nonlinear Liquid ChromatographyForssén, Patrik January 2005 (has links)
This thesis concerns the development and validation of methods for the industrially important area of adsorption isotherm parameter estimation in preparative, nonlinear high performance liquid chromatography (HPLC). Preparative chromatography is a powerful separation method to get pure compounds from more or less complex liquid mixtures, e.g., mixtures of mirror-image molecules. Computer simulations can be used to optimize preparative chromatography, but then competitive adsorption isotherm parameters are usually required. Here two methods to estimate adsorption isotherm parameters are treated: (i) the perturbation peak (PP) method and (ii) the inverse method (IM). A new theory for the PP method was derived and led to a new injection technique which was validated experimentally. This injection technique solved the severe problem with vanishing peaks and enabled us to use the PP method to estimate binary competitive adsorption isotherms valid over a broad concentration range. Also, the injection technique made it possible to estimate competitive adsorption isotherms for a quaternary mixture for the first time. Finally, an interesting perturbation peak phenomenon, known as the “Helfferich Paradox”, was experimentally verified for the first time. The IM is a relatively new method to determine adsorption isotherm parameters. It has the advantage of requiring very small samples, but also requires an advanced computer algorithm. An improved implementation of this computer algorithm was developed and tested experimentally. Also, a variant of the IM called “the inverse method on plateaus” was tested experimentally and the estimated adsorption isotherm parameters were shown to be valid over a broader concentration range than those estimated with the standard IM.
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Furan measurement in transformer oil by UV-Vis spectroscopy using fuzzy logic approachLai, Sin Pin January 2009 (has links)
An Ultraviolet to Visible (UV-Vis) spectroscopic analysis based on fuzzy logic approach has been developed for furan content measurement in transformer oil. Following the successful identification and quantification of furan derivatives in transformer oil by ASTM D5837 standard, the new approach is able to approximate the furan content more conveniently and economically. As furan concentration level would determine the absorption intensity in UV-Vis spectral range, the fuzzy logic software model developed would exploit this characteristic to aggregate the furans content level in transformer oil. The UV-Vis spectral response at other ambient temperature is also studied. The proposed technique provides a convenient alternative to conventional method of furan measurement by High Performance Liquid Chromatography (HPLC) or Gas Chromatography Mass Spectrometry (GC/MS) in ASTM D5837 Standard.
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Chromium carcinogenesis characterization of DNA damaging intermediates by EPR ³¹P NMR, HPLC, ESI-MS and magnetic susceptibility /Marin Córdoba, Roberto. January 2010 (has links)
Thesis (Ph.D.)--Ohio University, March, 2010. / Title from PDF t.p. Includes bibliographical references.
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Ανάπτυξη μεθοδολογίας για τον ποιοτικό και ποσοτικό προσδιορισμό αλλαντοΐνης και γλυκολυκού οξέως σε εκκρίματα σαλιγκαριού και καλλυντικές κρέμες / Development of methodology for the qualitative and quantitative determination of allantoin and glycolic acid in snail secretions and cosmetic creamsEl Mubarak, Mohamed Ahmed 21 December 2012 (has links)
Η βλέννα του σαλιγκαριού έχει χρησιμοποιηθεί στην ιατρική από την αρχαιότητα από την εποχή του Ιπποκράτη, ο οποίος είχε προτείνει τη χρήση
της βλέννας για την καταπολέμηση του πόνου, εγκαυμάτων και άλλων
τραυμάτων. Πρόσφατη επιστημονική μελέτες του εκκρίματος του σαλιγκαριού Helix aspersa επιβεβαίωσαν ότι η βλέννα περιέχει ένα ασυνήθιστο συνδυασμό φυσικών προϊόντων με ευεργετικές και θεραπευτικές ιδιότητες στο ανθρώπινο δέρμα. Η βλέννα του σαλιγκαριού παρουσιάζει σημαντικό οικονομικό - εμπορικό ενδιαφέρον, ως προς την αξιοποίηση των
χημικών συστατικών της όπως η αλλαντοΐνη και το γλυκολικό οξύ που
χρησιμοποιούνται ευρύτατα ως δραστικά συστατικά κατά την παρασκευή
φαρμακευτικών και καλλυντικών προϊόντων.
Η αλλαντοΐνη είναι μία ετεροκυκλική οργανική ένωση που παράγεται από
την κατάλυση των πουρινών από το ένζυμο καταλάση. Παρουσιάζει μια
μακρά ιστορία όσον αφορά στη χρήση της σε μια ποικιλία από τοπικά φάρμακα και καλλυντικά προϊόντα για την περιποίηση του δέρματος. Το γλυκολικό οξύ είναι το μικρότερο α-υδροξύ - οξύ (AHA). Χάρη στην εξαιρετική ικανότητά του να διαπερνάει το δέρμα, βρίσκει εφαρμογές σε διάφορα
προϊόντα φροντίδας του δέρματος, για τη βελτίωση της εμφάνισης και της
υφής του δέρματος μειώνοντας ρυτίδες, ουλές ακμής, υπέρχρωση και άλλα
και σε άλλες δερματικές παθήσεις.
Στην παρούσα εργασία έγινε προσπάθεια ανάπτυξης μεθοδολογιών για τον
ποιοτικό και ποσοτικό προσδιορισμό της αλλαντοΐνης και του γλυκολικού οξέος. Με χρωματογραφία υψηλής απόδοσης (HPLC-DAD) σε στήλη Synergi RP (Phenomenex ®) επετεύχθη πολύ καλός διαχωρισμός εντός 6
min. Οι τελικές συνθήκες διαχωρισμού (ισοκρατική έκλουση με εκλούτη
ρυθμιστικό διάλυμα 10 mM KH2PO4 pH 2.7 και η ροή ρυθμίστηκε στο 0.7 mL/min και στους 30 C) και προκατεργασίας δείγματος (αραίωση της
βλέννας στο ρυθμιστικό διάλυμα, θέρμανση στους 60 C για 20 λεπτά και εκχύλιση με εξάνιο) επιλέχθηκαν μετά από μελέτη διαφόρων παραμέτρων που αφορούν στη σύσταση του εκχυλιστικού μέσου και της κινητής φάσης. Η μέθοδος επικυρώθηκε ως προς τα αναλυτικά της χαρακτηριστικά (γραμμικότητα, επαναληψιμότητα, ακρίβεια και σταθερότητα).
Ανάλυση της βλέννας του σαλιγκαριού Helix aspersa έδειξε ότι περιέχει
48.610 ± 0.002, 47.590 ± 0.001, 52.820 ± 0.001 mg/L αλλαντοΐνης και
3753.01 ± 0.01, 3170.51 ± 0.02, 1979.23 ± 0.02 mg/L γλυκολικού οξέος
για τις τρεις παρτίδες που αναλύσαμε, αντίστοιχα.
Η προτεινόμενη μεθοδολογία χρησιμοποιήθηκε για την ποσοτική ανάλυση
τριών καλλυντικών κρεμών (Elicina της εταιρίας Cosméticos Elicina Ltda,
Santiago, Χιλή, Labcconte της εταιρίας Cosméticos Concepción Ltda, Χιλή
και μια κρέμα από την εταιρία Helix ir στην Κρήτη) στις οποίες η βλέννα
του σαλιγκαριού αναγράφεται να περιέχεται σε υψηλό ποσοστό (85%).
Τα αποτελέσματα μας δείχνουν ότι τα καλλυντικά σκευάσματα περιέχουν
0.110 ± 0.003, 0.260 ± 0.010 , 0.370 ± 0.001 mg/L αλλαντοΐνης και 4.520
± 0.010, 5.350 ± 0.010, 5.690 ± 0.001 mg/L γλυκολικού οξέος, αντίστοιχα. / The snail mucus has been used in medicine since the time of Hippocrates,
who proposed the use of mucus to combat pain, burns and other wounds.
Recent scientific studies of the snail secretion Helix Aspersa confirmed
that the snail contains an unusual combination of natural products which
are beneficial for human skin. The last time the mucus of the snail has important
economic - commercial interest in the use of chemical components
such as allantoin and glycolic acid are widely used as active ingredients in
the manufacture of pharmaceutical and cosmetic products.
Allantoin is a heterocyclic organic compound produced by the breakdown
of purines by the enzyme catalase. It has a long history in the use of a variety
of topical medications and cosmetics for skin care. The glycolic acid
is the smallest alpha-hydroxy acid (AHA). Thanks to its excellent ability
to penetrate the skin, it finds applications in various skin care products, for
improving the appearance and texture of skin by reducing wrinkles, acne
scars, hyperpigmentation and also can improve many other skin disorders.
In this study we developed analytical methodology for qualitative and quantitative
determination of allantoin and glycolic acid. Application of highperformance
chromatography (HPLC-DAD) on a Synergi RP (Phenomenex
®) column has provided a very good separation within 6 min. The final separation
(isocratic elution with buffer 10 mM KH2PO4 pH 2.7 as eluent and
flow rate 0.7 mL/min at 30 °C) and sample pretreatment (by dilution the
mucus in the buffer, heated at 60 °C for 20 min and extracted with hexane)
were selected after a study of various parameters relating to the extraction
medium and the mobile phase. The method was validated in terms of
analytical characteristics (linearity, repeatability, accuracy and stability).
Analysis of the snail secretions Helix aspersa showed that it contains 48.610
± 0.002, 47.590 ± 0.001, 52.820 ± 0.001 mg/L allantoin and 3753.01 ± 0.01,
3170.51 ± 0.02, 1979.23 ± 0.02 mg/L glycolic acid for three batches that
we analyzed, respectively.
The methodology was used for quantitative analysis of three cosmetic creams
(Elicina from the company: Cosméticos Elicina Ltda, Santiago, Chile, Labcconte
from the comany: Cosméticos Concepción Ltda, Chile and a cream
from the company: Helix ir in Crete) where the snail mucus is deemed to
be about 85%. Our results show that cosmetic products contain 0.110 ±
0.003, 0.260 ± 0.010 , 0.370 ± 0.001 mg/L allantoin and 4.520 ± 0.010,
5.350 ± 0.010, 5.690 ± 0.001 mg/L glycolic acid, respectively.
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Efeito de tratamentos pós-polimerização sobre o peso molecular, o grau de conversão, a temperatura de transição vítrea e a liberaçãp in vitro de monômero residual, plastificante e produtos de degradação de resinas acrílicas para reembasamento imediatoUrban, Vanessa Migliorini [UNESP] 11 January 2007 (has links) (PDF)
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urban_vm_dr_arafo.pdf: 2869944 bytes, checksum: e7264bf2de7fc0a0dde924482741fd32 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os objetivos deste estudo foram avaliar: 1. o efeito de tratamentos póspolimerização (MW-irradiação por energia de microondas e WB-imersão em água aquecida) sobre o grau de conversão (DC) de resinas acrílicas para reembasamento imediato (Ufi Gel hard-U, Kooliner-K e Tokuso Rebase Fast-T) e de uma resina acrílica para base de prótese (Lucitone 550-L), submetida a dois ciclos de polimerização (LS-curto e LL-longo) por espectroscopia FT-Raman; 2. o peso molecular (M w) do pré-polímero dos materiais U, K, T e L e das amostras polimerizadas da resina K (controle; MW e WB) por GPC; 3. o efeito de MW e WB na temperatura de transição vítrea (Tg) das resinas para reembasamento imediato (Duraliner II-D, K, New Truliner-N, U e T) e da resina para base de prótese (LS e LL) por DSC; 4. o efeito de WB na liberação de compostos residuais (isobutil metacrilato-IBMA, 1,6-hexanediol dimetacrilato-1,6-HDMA e DBNP-dibutil-n-ftalato) a partir das resinas para reembasamento imediato K, N, U e T para saliva artificial por CLAE; 5. o efeito de WB na liberação de produtos de degradação (ácido metacrílico-MA e ácido benzóico-BA) a partir das resinas para reembasamento imediato K, N, U e T para saliva artificial por CLAE. Amostras do grupo controle não foram submetidas a nenhum tratamento. Os resultados de DC (%) foram analisados pelo teste de Kruskal-Wallis ( =0,05). Os resultados de Tg (ºC) foram analisados pela análise de variância (ANOVA), seguido pelo teste de Tukey ( =0,05). Os resultados da liberação de monômero ' 224 residual e plastificante (μg/mL) foram submetidos aos testes de Wilcoxon ou de Mann-Whitney ( =0,05). Os resultados da liberação de produtos de degradação (μg/mL) foram submetidos aos testes de Wilcoxon, Mann-Whitney ou Kruskal- Wallis ( =0,05). Para as amostras do grupo controle, não houve diferenças significantes entre o DC das resinas U e LL e entre... / The aims of this study were to evaluate: 1. the effect of post-polymerization treatments (MW-microwave irradiation and WB-water-bath) on the degree of conversion (DC) of reline resins (Ufi Gel hard-U, Kooliner-K, and Tokuso Rebase Fast-T) and denture base resin (Lucitone 550-L), submitted to two polymerization cycles (LS-short and LL-long) by FT-Raman spectroscopy; 2. the molecular weight (M w) of the powder of U, K, T, and L materials and of K polymerized specimens (control; MW; and WB) by GPC; 3. the effect of MW and WB on the glass transition temperature (Tg) of the reline resins (Duraliner II-D, K, New Truliner-N, U and T) and the heat-polymerized resin (LS and LL) by DSC; 4. the effect of WB on the leaching of residual compounds (isobutyl methacrylate- IBMA, 1,6-hexanediol dimethacrylate-1,6-HDMA, and DBNP-dibutyl-nphthalate) from the reline resins (K, N, U, and T) in artificial saliva by HPLC; 5. the effect of WB on the leaching of degradation products (methacrylic acid-MA and benzoic acid-BA) from the reline resins K, N, U, and T in artificial saliva by HPLC. Control group specimens were left untreated. DC (%) data were analyzed using Kruskal-Wallis test (_=.05). Tg (ºC) data were analyzed using ANOVA/Tukey's test (_=.05). The results (æg/mL) of residual monomer and plasticizer leachability were submitted to Wilcoxon or Mann-Whitney tests (_=.05). The results (æg/mL) of degradation products leachability were submitted to Wilcoxon, Mann-Whitney or Kruskal-Wallis tests (_=.05). For DC control specimens, there were no significant differences between U and LL and among LL, K, and T. LS specimens had the highest DC. Only material K exhibited an increased DC after WB. All powders had M w from 4.0x105 to 6.5x105 and narrow M w distributions (2.1 to 3.6). Polymerization and post-polymerization produced K specimens with M w values similar to that of K powder...(Complete abstract, click electronic address below).
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Caracterização físico-química, desenvolvimento e validação de métodos analíticos para o extrato seco dos bulbos da espécie Rhodophiala bifida (Herb.) Traub com alto teor do alcaloide MontaninaAraújo, Mariele Brambilla de January 2017 (has links)
Os alcaloides têm apresentado diversas atividades biológicas. Entre eles, a montanina vem demonstrando um bom desempenho nesse sentido, como, atividade antioxidante, ação inibitória do crescimento de culturas bacterianas e importante atividade de inibição do crescimento de linhagens tumorais. Atualmente, não existem muitos relatos da sua caracterização ou métodos analíticos quantitativos disponíveis na literatura para atribuir seu teor. Assim, após purificação, a caracterização da montanina foi realizada por calorimetria exploratória diferencial (DSC), espectroscopia na região do ultravioleta (UV), infravermelho (IV), espectrometria de massas (CLAE-EM), ressonância magnética nuclear de hidrogênio (RMN1H), de carbono (RMN13C) e em 2D homo e heteronucleares tais como COSY (nJH-H, escalar), NOESY (nJH-H, dipolar), HSQC (1JH-C, escalar) e HMBC (nJH-C, escalar). Na sequência, foram desenvolvidos métodos empregando a cromatografia líquida de alta eficiência (CLAE) acoplada aos detectores ultravioleta e aerossol carregado (CLAE- UV/DAC) para a quantificação da montanina. Os mesmos foram validados, avaliando-se os parâmetros de especificidade, linearidade, intervalo, limite de detecção, limite de quantificação, precisão, exatidão e robustez. Os resultados obtidos foram avaliados por estatística descritiva e os métodos comparados pelo resultado da análise de variância (ANOVA). Desse modo, foram desenvolvidos procedimentos que podem ser aplicados para aprimorar o controle de qualidade, contribuindo para assegurar a eficácia terapêutica da montanina. / Alkaloids have several biological activities. Among them, montanine have shown antioxidant activity, inhibitory effect on bacterial growth and important activity inhibiting growth of some tumor cell lines. Currently, there are a few reports about its characterization as well as quantitative analytical methods to determine its purity. Thus, after a purification step, montanine will be characterized by its differential scanning calorimetry (DSC), ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (HPLC-MS), nuclear magnetic resonance of proton (NMR1H), carbon (NMR13C) and 2D homo and heteronuclear such as COSY (nJH-H, scalar), NOESY (nJH-H, dipolar), HSQC (1JH-C, scalar) and HMBC (nJH-C, scalar). Further, quantitation methods will be developed employing high-performance liquid chromatography (HPLC) coupled with ultraviolet and charged aerosol detectors (HPLC-UV/CAD). These methods will be validated regarding the parameters specificity, linearity, range, detection limit, quantitation limit, precision, accuracy and robustness. The results will then be evaluated by descriptive statistics and the developed methods will be compared using analysis of variance (ANOVA). Therefore, tests will be developed that can be used to improve quality control, helping to ensure the therapeutic efficacy of montanine.
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Entacapona : desenvolvimento e validação de métodos analíticos, método de dissolução e estudo preliminar de estabilidade / Entacapone : development and validation of analytical methods, dissolution method and preliminary study of stabilityPaim, Clésio Soldateli January 2007 (has links)
Entacapona, inibidor da catecol-o-metiltransferase, é utilizada como terapia adjuvante à associação de levodopa + carbidopa no tratamento da doença de Parkinson. No Brasil encontra-se disponível na forma de comprimidos revestidos com o nome comercial de Comtan®. O objetivo desse trabalho foi desenvolver e validar métodos analíticos para o controle de qualidade da entacapona em comprimidos revestidos e método de dissolução, bem como, estudos preliminares de estabilidade durante o desenvolvimento do método indicativo de estabilidade por cromatografia líquida de alta eficiência (CLAE) e na determinação da cinética de fotodegradação. Devido à falta da substância química de referência de entacapona, realizou-se a extração do fármaco a partir dos comprimidos e a caracterização qualitativa e quantitativa por calorimetria diferencial de varredura (DSC), espectrofotometria na região do infravermelho (IV), ressonância magnética nuclear (RMN) e volumetria em meio não-aquoso. Métodos utilizando cromatografia em camada delgada (CCD), espectrofotometria na região do ultravioleta (UV) e CLAE foram utilizados para análise qualitativa de entacapona. A validação dos métodos para determinação quantitativa (UV e CLAE) foi realizada de acordo os parâmetros das principais Guias Oficiais (BRASIL, 2003; ICH, 2005; USP 30, 2007). O método de dissolução foi desenvolvido e validado de acordo com a USP. Os métodos qualitativos e quantitativos descritos nesse trabalho demonstraram-se adequados para determinação de entacapona em comprimidos revestidos. Para o método de dissolução as seguintes condições foram selecionadas: solução tampão acetato pH 5,3 como meio, utilizando pás a 50 rpm. A cinética de fotodegradação em metanol, frente à luz UV indicou reação de segunda ordem. Análises por CLAE-EM/EM sugerem que o produto de fotodegradação formado seja o isômero geométrico de entacapona (Z-entacapona). / Entacapone, inhibitor of the catechol-O-methyltransferase, is used as adjunct with levodopa + carbidopa association in the treatment of Parkinson’s disease. In Brazil it is available in tablets coated with the commercial name of Comtan®. The aim of this work was to develop and validate analytical methods for the quality control of entacapona in coated tablets, as well as, preliminary studies of stability during the development of stability-indicating high-performance liquid chromatography (HPLC) method and determination of photodegradation kinetics. Due to the lack of entacapone reference standard, it was necessary to extract the drug by the tablets and the qualitative and quantitative characterization was carried out by differential scanning calorimetry (DSC), infrared spectroscopy (IR), nuclear magnetic resonance (NMR) and non-aqueous titration of weak acid. Methods using thin-layer chromatography (CCD), ultraviolet spectroscopy (UV) and HPLC were performed to entacapone qualitative analysis. The validation of the methods for quantitative determination (UV and CLAE) was accomplished of agreement the parameters of the main Official Guides (BRASIL, 2003; ICH, 2005; USP 30, 2007). The dissolution test was developed and validate in according by USP. The qualitative and quantitative methods described in this study demonstrated to be adequate to determination of entacapone in coated tablets. For dissolution test the following conditions were selected: buffer acetate pH 5,3 as medium, using paddles at 50 rpm. The photodegradation kinetics in methanol, front to UV light indicated the second-order reaction. LC-MS/MS method results suggest that the photodegration product was the geometric isomer of entacapone (Z-entacapone).
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[en] EVALUATION OF THE CONTAMINATION FROM GUANABARA BAY MANGROVES USING CRABS UCIDES CORDATUS AS INDICATORS OF OIL POLLUTANTS AND DEVELOPMENT OF ANALYSIS / [pt] AVALIAÇÃO DA CONTAMINAÇÃO DE MANGUEZAIS DA BAÍA DE GUANABARA UTILIZANDO CARANGUEJOS UCIDES CORDATUS COMO BIOINDICADOR DE POLUENTES DE PETRÓLEO E DESENVOLVIMENTO DE METODOLOGIAS DE ANÁLISESADRIANA HADDAD NUDI 07 March 2006 (has links)
[pt] O principal objetivo deste estudo foi validar o
caranguejo
da espécie Ucides
cordatus como organismo indicador de poluição por óleo
em
áreas de
manguezais da Baía de Guanabara. Para isto foram
realizadas as seguintes
etapas: (1) análises químicas de hidrocarbonetos
policíclicos aromáticos (HPAs)
em amostras de hepatopâncreas e sedimento por
cromatografia gasosa acoplada
ao espectrômetro de massas (CG/EM); (2) bioensaios com
experimentos de
exposição ao pireno e avaliação das respostas biológicas
através das medidas
dos metabólitos formados em amostras de urina de
caranguejos; (3) ensaio do
micronúcleo em hemócitos de caranguejos para verificar
conseqüências
genotóxicas. Amostras de sedimento e caranguejos foram
coletadas entre
setembro de 2003 e outubro de 2004 em quatro áreas de
manguezais da Baía de
Guanabara: Piedade, Nova Orleans, Suruí e Canal do
Peteca.
O manguezal de
Barra de Guaratiba foi escolhido como área de referência
fora da baía. Foi
desenvolvido um método semiquantitativo e não destrutivo
para medidas de
metabólitos em urina de caranguejo utilizando
cromatografia líquida de alta
eficiência com detector de fluorescência (CLAE/F). Esta
técnica apresentou boa
sensibilidade (LQ= 0,01 (mi)g mL-1) e baixo custo.
Amostras
de urina de
caranguejos foram analisadas em todas as áreas estudas.
Foram conduzidos
vários bioensaios em laboratório com caranguejos
expostos
à pireno. Durante as
primeiras etapas dos experimentos, o metabólito 1-pireno-
sulfato foi o principal
metabólito formado. Em urina de caranguejos dos
manguezais
estudados, o 1-
pireno-glucosídeo foi o metabólito dominante. Foram
encontradas diferenças significativas nos níveis de HPAs
totais em amostras de hepatopâncreas,
variando de 256 (mi)g kg-1 (p.s.) para Barra de Guaratiba
a
67000 (mi)g kg-1 (p.s.) no
Suruí. Os manguezais de Suruí e do Canal do Peteca
apresentaram as maiores
concentrações de HPAs nas amostras de hepatopâncreas e
sedimento. Os
compostos de 3 a 4 anéis aromáticos foram mais
abundantes que os HPAs de 5
e 6 anéis. As concentrações de HPAs nas amostras de
sedimento diminuíram
com a profundidade em todas as estações estudadas. As
concentrações
determinadas foram: Barra de Guaratiba ((somatório)PAH 35-
200 (mi)g
kg-1p.s); Piedade
((somatório)PAH 311-615 (mi)g kg-1 p.s.); Nova Orleans
((somatório)PAH 270-1134
(mi)g kg-1 p.s.);
Suruí ((somatório)PAH 1280-31500 (mi)g kg-1 p.s.) e no
Canal do
Peteca ((somatório)PAH 336-6000
(mi)g kg-1 p.s.). Amostras de hepatopâncreas de Ucides
cordatus apresentaram
maiores concentrações de HPAs que as de sedimento. O
fator de bioacumulação
(FA) variou entre 0,7 e 35, e fator de bioacumulação
biota-sedimento (FBA)
entre 0,02 e 3,0. Foram encontradas correlações
positivas (r2= 0.70) entre os
metabólitos de pireno em urina e os níveis de HPAs em
hepatopâncreas e
sedimento dos locais estudados. O ensaio do micronúcleo
foi realizado no
laboratório, em caranguejos expostos ao pireno. Foi
observado um aumento do
número de micronúcleos nos hemócitos, indicando
respostas genotóxicas e
mutagênicas. Entretanto, o ensaio do micronúcleo não foi
sensível para avaliar
o gradiente de contaminação nos manguezais amostrados,
não apresentando
correlação com os níveis de contaminação detectados nas
amostras de
hepatopâncreas e sedimento. O Ucides cordatus demonstrou
ser um excelente
bioindicador para avaliar a qualidade ambiental em áreas
de manguezais. / [en] The aim of this study was the validation of crab Ucides
cordatus as indicator of
oil pollution in mangrove areas from Guanabara Bay. For
such purpose it was
performed: (1) chemical analyses of PAHs in hepatopancreas
and sediment
samples by gas chromatography with mass spectrometer
detector (GC/MS); (2)
bioassays with pyrene exposure experiments and evaluation
of biological
responses through pyrene metabolites measurements in urine
samples; (3)
micronucleus assay in crab hemocytes to verify genotoxic
consequences.
Sediment and crab samples were collected from September
2003 to October 2004
in four mangrove areas of Guanabara Bay: Piedade, Nova
Orleans, Suruí, Canal
do Peteca. The mangrove of Barra de Guaratiba was chosen
as reference site. It
was developed a semiquantitative and nondestructive method
for measurements of
pyrene metabolites in crab urine using HPLC/Fluorescence.
This technique
presented several advantages as sensitivity (DL= 0.01(mi)
g.mL-
1) and low cost.
Crabs urine was sampled straight from the field in all
studied sites. Beside this, it
was conducted several bioassays in laboratory with crabs
exposed to pyrene.
During the first stages of experiments, pyrene-1-sulphate
was the main metabolite
produced, followed by pyrene-1-glucoside. In crabs urine
from mangrove areas,
the pyrene-1-glucoside was the dominant metabolite. It was
found significant
differences on total PAH levels of crab samples among
studied sites, which
ranged from 256 in Barra de Guaratiba to 67000 (mi)g kg-1
dry
weight, in Suruí.
Suruí and Canal do Peteca presented the highest PAHs
concentrations in crab
hepatopancreas and sediment samples. Besides, three and
four ring compounds
were more abundant than five and six ring PAHs. In
sediment samples PAHs concentrations decreased with depth
for all studied sites: Barra de Guaratiba
((somatório)PAH 35-200 (mi)g kg-1d.w.); Piedade
((somatório)PAH 311-615 (mi)g kg-
1d.w.); Nova Orleans
((somatório)PAH 270-1134 (mi)g kg-1d.w.); Suruí (somatório)
PAH 1280-31500 (mi)g kg-
1d.w. and Peteca
((somatório)PAH 336-6000 (mi)g kg-1d.w.). Hepatopancreas
samples of
crabs Ucides cordatus
had higher PAHs concentrations than sediment samples with
bioaccumulation
factors (BAF) of 0,70 to 35,00 and 0,02 to 3,00 for the
bioaccumulation factors
biota-sediment (BSAF). Also, it was found high
correlations between pyrene
metabolites in urine and PAHs levels in crab
hepatopancreas and sediments.
Pyrene metabolites of crab urine samples presented strong
correlation (r2= 0,77)
with hepatopancreas and sediment samples from each studied
site. In laboratory,
micronucleus assay was performed in crabs exposed to
pyrene. It was found an
increase of micronucleus number in haemocytes, indicating
responses of
genotoxicity and mutagenicity. However, the micronucleus
assay was not
sensitive enough for showing contamination gradient among
mangrove sites, nor
it was significantly correlated with PAHs levels of crabs
and sediment samples.
Ucides cordatus revealed an excellent bioindicator and
suitable for monitoring the
environmental quality in mangrove areas.
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