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Evaluation de l’électrophorèse capillaire comme technique d’analyse des antipaludiques retenus dans le schéma thérapeutique ivoirien / Evaluation of capillary electrophoresis as an analytical technique of antimalarial drugs recommended in the ivorian therapeutic protocolAmin, N'Cho Christophe 09 April 2013 (has links)
La nécessité de garantir la qualité des médicaments antipaludiques disponibles sur le marché pharmaceutique d'Afrique subsaharienne est l'une des stratégies mises en œuvre pour réduire les taux élevés de morbidité et de mortalité liés au paludisme. L'objectif de ce travail de thèse était de proposer des méthodes de dosage par électrophorèse capillaire (EC) de combinaisons antipaludiques à base de sulfadoxine/pyriméthamine (SDX/PYR), artésunate/amodiaquine (AS/AQ) et artéméther/luméfantrine (AM/LUM) retenues dans le schéma thérapeutique ivoirien et commercialisées sous forme de comprimés.Cet objectif a été atteint en employant trois modes de séparation : l'électrophorèse capillaire de zone (CZE) pour SDX/PYR, la chromatographie électrocinétique micellaire (MEKC) pour AS/AQ et la chromatographie électrocinétique par microémulsion (MEEKC) pour AM/LUM. Les méthodes développées ont été validées selon les règles d'ICH et appliquées à des comprimés provenant d'officines ou vendues sur les marchés de rue en Côte d'Ivoire. Elles présentent une répétabilité satisfaisante (CV < 3%, n = 7 procédures analytiques). La méthode de CZE qui utilise un tampon pH 7 pour la séparation de SDX et PYR a donné des résultats de dosage concordants avec la méthode de chromatographie liquide décrite dans l'USP-NF. Sur les neuf formulations de comprimés analysées, une formulation prélevée dans le marché de rue s'est révélée sous-dosée en SDX. La méthode MEKC utilisant le dodécylsulfate de sodium (SDS) dans un tampon borate pH 9,2 a permis le dosage d'AS et AQ. L'application à l'analyse de quatre formulations issues de l'officine a donné des teneurs en AS et AQ conformes aux teneurs déclarées. Enfin, la microémulsion octane-butanol-SDS-tampon borate en MEEKC s'est révélée appropriée au dosage d'AM et LUM, molécule très hydrophobe. L'application à l'analyse de quatre formulations prélevées à l'officine a révélé des teneurs conformes aux teneurs déclarées et la présence dans une formulation d'un ingrédient non déclaré. Le potentiel de screening de cette méthode MEEKC, évalué sur 22 antipaludiques et la sulfaméthoxazole et la triméthoprime, a donné une résolution partielle ou totale pour 17 composés.L'EC peut être utilisée comme technique alternative à la chromatographie liquide pour le contrôle des antipaludiques retenus dans le schéma thérapeutique ivoirien. / The need to ensure the quality of antimalarials available on the pharmaceutical market in sub-Saharan Africa is one of the strategies implemented to reduce the high morbidity and mortality rates associated with malaria. The aim of this thesis was to propose capillary electrophoresis (CE) methods for the determination of combinations of antimalarials containing sulfadoxine/pyrimethamine (SDX/PYR), artesunate/amodiaquine (AS/AQ) and artemether/lumefantrine (AM/LUM) recommended in the Côte d'Ivoire therapeutic protocol and marketed as tablets.The objective was achieved by employing three separation modes: capillary zone electrophoresis (CZE) for SDX/PYR, micellar electrokinetic chromatography (MEKC) for AS/AQ and microemulsion electrokinetic chromatography (MEEKC) for AM/LUM. The developed methods were validated according to ICH rules and were applied to various tablet formulations bought in pharmacies or on the street-market in Côte d'Ivoire. The methods presented satisfactory repeatability values (CV <3%, n = 7 analytical procedures). CZE method used a buffer of pH 7 for the simultaneous separation of SDX and PYR and gave results that were compliant with the dosage by the liquid chromatography method described in the U.S. Pharmacopoeia. Of the nine tablet formulations analyzed, one formulation bought on the street-market had a low SDX content. An MEKC method using SDS in a borate buffer pH 9.2 allowed the determination of AS and AQ in bilayer tablets. Application to four commercial formulations with different dosages gave a content in good agreement with the declared content. Finally, butanol-octane-SDS-borate buffer microemulsion in MEEKC was found to be suitable for the determination of AM and LUM, a very hydrophobic compound. Application to four commercial tablet formulations gave a content in good agreement with the declared content and evidenced the presence in a formulation of an undeclared ingredient. The potential screening capacity of this MEEKC method was evaluated on 22 antimalarials and on sulfamethoxazole and trimethoprim. Partial or complete resolution of 17 compounds was obtained.CE can be used as an alternative technique to liquid chromatography for the control of antimalarial drugs recommended in the national therapeutic protocol against malaria.
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Desenvolvimento de um método para determinação de ácidos orgânicos em sucos de frutas utilizando Eletroforese Capilar de Zona (ECZ) / DEVELOPMENT OF A METHOD FOR DETERMINATION OF ORGANIC ACIDS IN FRUIT JUICES USING CAPILLARY ZONE ELECTROPHORESIS (ECZ)Carvalho, José Marcos Valentim de 09 March 2010 (has links)
An electrophoretic methodology with UV detection was developed for determinations the main organic acids contained in fresh fruit juice and industrialized fruits juices produced in Sergipe/Brazil and sold in markets and supermarkets of Lagarto, Itabaiana and Aracaju. Oxalic, tartaric, citric, gallic and ascorbic (L aa) organic acids were separate and quantified in grape, orange, lemon, carambola, umbu-caja, acerola, cashew, strawberry samples
of fresh juices and samples of mixed juice industrialized (mixed acerola, orange, fortified whit L aa; mixed apple, orange, tangerine and lemon; mixed orange, lemon and tangerine; guava juice and mixed apple, lemon and grape). The analyses were made employing BGE containing 100 mmol/L borate buffer pH 10.0 and 0.5 mmol/L cetyl trimethyl ammonium bromide (CTAB) as EOF-modifier, a fused silica capillary of 59 cm of length (23.7 cm effective, 75 mm of i.d.) = 214 nm. The sample injection was made in hydrodynamic mode (height 4.5 cm) for 15 s, the method was linear within 0.0040 to 0.0450 g/100mL. The calibration curves were prepared with the addition of external standard, with correlation coefficient from 0.9912 to 0.9995, the precision ranged of 1.48 to 11.46% (n= 3). The limit of detection varied from 0.0005 to 0.0155 g/100mL and the limit of quantification varied
from 0.0016 to 0.0517 g/100mL. The recoveries in samples of fresh juices were 83.6 to 117.5% (n = 50) and from 83.60 to 108.7% (n=11) for the acids in fruits juices industrialized samples. The oxalic, tartaric, citric, and L aa were separated and quantified in samples of fresh juices while citric and L aa acid in samples of industrialized juices there was reduction in the concentration of 18.90%, 28.20% and 36.00% L - aa of juices of fresh acerola, orange and cashew respectively and of 100.0%, 99.40% in samples of mixed juice industrialized, mixed apple, orange, tangerine and lemon,
mixed acerola, orange, fortified whit L aa respectively, was also reduction the concentration of citric acid in two samples juice industrialized 15,20% in mixed apple juice, orange, tangerine, lemon and 56,9% in guava juice. The proposed method is rapid and sensitive and can be used to analysis of
organic acids in juice fruit samples. / Uma metodologia eletroforética com detecção no UV foi desenvolvida para determinação dos ácidos orgânicos contidos em sucos de frutas frescos e em sucos de frutas industrializados produzidos em Sergipe/Brasil e comercializados nos mercados e supermercados de Lagarto, Itabaiana e
Aracaju. Os ácidos orgânicos: oxálico, tartárico, cítrico e o ácido ascórbico (L aa) foram separados e quantificados em amostras de sucos frescos de uva, laranja, limão, carambola, umbu-cajá, acerola, caju, morango e em amostras de sucos industrializados (misto de acerola, laranja fortificado com
L aa; misto de maçã, laranja, tangerina e limão; misto de laranja, limão e tangerina; suco de goiaba e misto de maçã, limão e uva). As análises foram realizadas empregando uma solução tampão contendo 100 mmol/L de tampão borato pH 10,0 e 0,5 mmol/L de brometo de cetiltrimetilamônio (CTAB) como inversor do fluxo eletroosmótico, um capilar de sílica fundida de 59 cm de comprimento (23,7cm efetivo, 75 μm de d.i.) e detecção a l=214nm. A injeção da amostra foi feita no modo hidrodinâmico (altura de 4,5 cm) por 15 s. O método mostrou-se linear numa faixa de 0,0040 a 0,0450 g/100 mL, as curvas de calibração foram preparadas com adição de padrão externo, com coeficiente de correlação de 0,9912 a 0,9995, a precisão variou de 1,48 a 11,46% (n = 3), o limite de detecção variou de 0,0005 - 0,0155 g/100mL e o de quantificação 0,0016 - 0,0517 g/100 mL. As recuperações
dos ácidos nas amostras de sucos frescos variaram de 83,60 a 117,5% (n = 50), e de 83,60 a 108,7% (n=11) para os ácidos nas amostras de sucos industrializados. Os ácidos, oxálico, tartárico, cítrico e L aa foram separados e quantificados nas amostras de sucos frescos, enquanto que os
ácidos, cítrico e L aa, nas amostras de sucos industrializados, sendo que houve redução na concentração do ácido ascórbico de 18,90%, 28,20% e 36,00% nos sucos frescos de acerola, laranja e caju respectivamente, e de
100,0% no suco industrializado misto de maça, laranja, tangerina, limão e 99,40% no suco industrializado misto de acerola, laranja enriquecido com L aa, houve também redução na concentração do ácido cítrico em duas amostras de sucos industrializados, 15,20% e 56,90% nos sucos, misto de maçã, laranja, tangerina, limão, e no de goiaba. O método desenvolvido foi rápido, sensível e adequado para análise de ácidos orgânicos em amostras de sucos de frutas.
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