27 research outputs found
Contribution à l'amélioration de modèles pour estimer les paramètres de stabilité de substances médicamenteuses :cas particuliers de l'acide acétylsalicylique
No full textDoctorat en sciences pharmaceutiquesinfo:eu-repo/semantics/nonPublishe
An original algorithm for non linear parameter estimation of drug stability data
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A new method for pH-profile data treatment: Non linear parameter estimation
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Greening Reversed-Phase Liquid Chromatography Methods Using Alternative Solvents for Pharmaceutical Analysis
No full textThe greening of analytical methods has gained increasing interest in the field of pharmaceutical analysis to reduce environmental impacts and improve the health safety of analysts. Reversed-phase high-performance liquid chromatography (RP-HPLC) is the most widely used analytical technique involved in pharmaceutical drug development and manufacturing, such as the quality control of bulk drugs and pharmaceutical formulations, as well as the analysis of drugs in biological samples. However, RP-HPLC methods commonly use large amounts of organic solvents and generate high quantities of waste to be disposed, leading to some issues in terms of ecological impact and operator safety. In this context, greening HPLC methods is becoming highly desirable. One strategy to reduce the impact of hazardous solvents is to replace classically used organic solvents (i.e., acetonitrile and methanol) with greener ones. So far, ethanol has been the most often used alternative organic solvent. Others strategies have followed, such as the use of totally aqueous mobile phases, micellar liquid chromatography, and ionic liquids. These approaches have been well developed, as they do not require equipment investments and are rather economical. This review describes and critically discusses the recent advances in greening RP-HPLC methods dedicated to pharmaceutical analysis based on the use of alternative solvents
Innovative and green analytical methods for quality control of essential medicines : application to antimalarial drugs
No full textLe contrôle qualité des médicaments est une étape essentielle de la chaine de distribution des médicaments. Il garantit leurs fiabilités avant leurs utilisations et contribue à la lutte contre les médicaments falsifiés ou de qualité inférieure. Il est conventionnellement réalisé selon les méthodes des monographies des pharmacopées. Ces méthodes se caractérisent souvent par la complexité de leur mise en œuvre et des temps longs consacrés à leurs réalisations. Surtout, ces méthodes nécessitent souvent l’utilisation de réactifs et solvants toxiques pour le personnel de laboratoire et l’environnement.L’objectif de ce travail est de contribuer à l’amélioration du contrôle qualité des médicaments à travers le développement de méthodes d’analyses peu polluantes et de mise en œuvre facile et faisable dans les laboratoires dont ceux à ressources limitées. Il s’est agi en particulier de développer des méthodes de chromatographie liquide haute performance à polarité de phases inversée avec des phases mobiles à base d’éthanol qui est l’un des solvants les plus verts. Pour faire la preuve de la pertinence de cette approche, des formulations d’antipaludiques à base d’artésunate et d’amodiaquine d’une part, et d’artéméther et de luméfantrine d’autre part, ont été choisis.La première partie du travail a commencé par une étude de criblage utilisant l’éthanol comme solvant organique afin d’évaluer l’effet de différents paramètres critiques tels que le pH et la nature de la phase stationnaire sur le comportement chromatographique des molécules en termes de symétrie de pic, de rétention et de détection. L’association artésunate/amodiaquine a été choisie comme preuve de concept car il s’agit d’un modèle intéressant impliquant une molécule à caractère acide avec peu de groupements chromophores et une molécule à caractère basique. Les résultats du criblage ont permis d’optimiser différentes méthodes en phase inverse vertes à base d’éthanol permettant d’analyser l’artésunate, l’amodiaquine et leurs impuretés. L’approche « Quality by Design » recommandée par les autorités règlementaires pharmaceutiques et permettant d’obtenir des méthodes plus flexibles et robustes, a été choisi comme stratégie de développement. Les méthodes ont été ensuite validées selon le guide ICH Q2 (R1), en utilisant la stratégie du profil d’exactitude.La deuxième partie du travail a consisté à démontrer le potentiel d’un spectromètre proche infrarouge portable et à bas prix, en association avec les outils chimiométriques, dans la détection de médicaments falsifiés. L’analyse a porté sur l’association artémether/luméfantrine qui est l’un des médicaments antipaludiques les plus falsifiés. Malgré sa zone spectrale réduite et sa faible résolution comparativement aux appareils classiques, le spectromètre portable a permis de détecter des médicaments falsifiés ne contenant aucune substance active et d’identifier spécifiquement les différentes marques de comprimés. Les résultats obtenus ont démontré le grand potentiel de ces nouveaux équipements proche infrarouge innovants et à bas prix pour leur utilisation en première ligne dans la détection et la lutte contre les faux médicaments. Afin de mieux interpréter les résultats de l’analyse proche infrarouge, une méthode de chromatographie liquide en phase inverse, verte et rapide a été aussi développée pour doser l’artéméther et la luméfantrine dans les comprimés.Ces différentes approches ont montré qu’il est possible de mettre en œuvre le concept de chimie analytique verte pour le contrôle qualité sans nécessité l’acquisition de nouveaux équipements pour obtenir des méthodes performantes qui respectent la règlementation pharmaceutique.The quality control of pharmaceutical products is a key issue in the medicine supply chain. It guarantees the reliability before consumption and contribute to fight against substandard and falsified drugs. It is conventionally performed according to pharmacopeias in which methods are most often long and use harmful reagents for the technical staff, health, and environment.The objective of this work was to improve the quality control of drugs through the development green analytical methods easy to implement in laboratories including those with limited resources. It was consisted, particularly, to develop reversed phase-high performance liquid chromatography methods with mobile phases based on ethanol which is one the best green solvents. Analyzes were applied to the antimalarial combination therapies such as artesunate/amodiaquine and artemether/lumefantrine.The first part of the study started by a screening phase where impacts of critical parameters, such as mobile phase pH and stationary phase, on compound peak symmetry, retention and detection were investigated. Artesunate/amodiaquine combination therapy, which includes an acidic compound with few chromophores and a basic compound was chosen as proof of concept. Several pH modifiers selected for their ecofriendly character and stationary phases were screened. Based on the screening results, different green RP-HPLC methods using ethanol as organic solvent et allowing to analyze artesunate, amodiaquine and their related impurities were developed. Quality by Design approach, recommended by the pharmaceutical regulatory authorities and allowing to obtain robust methods, was chosen as development strategy. Developed methods were validated according ICH Q2 (R1) guideline by using accuracy profile methodology.The second part of the study consisted in investigating the qualitative performance of a low-cost handheld near infrared spectrophotometer associated to chemometric methods as screening tool in the identification of falsified drugs. Analysis was performed on artemether/lumefantrine tablets which are one of the most falsified drugs, Despite its limited spectral range and low resolution compared to bench top devices, the handheld device allowed to detect falsified drugs with no active ingredients and to identify specifically a tablet brand name. This innovated low-cost handheld near infrared spectrophotometer offers a promising performance and could be used as a first line screening tool in the detection and fight against falsified drugs. For a better interpretation of the near infrared results, a green and fast HPLC method was also developed, validated, and used to analyze artemether and lumefantrine in the tablets.These different approaches demonstrated that green analytical methods could be implemented in the pharmaceutical quality control field without the need of new equipment and with analytical performances in accordance with pharmaceutical requirements
Incorporating batch effects in the estimation of drug stability parameters using an Arrhenius model
No full textThe nonlinear estimation of drug stability parameters (energy of activation E(a) and shelf-life t(Y)) by conventional approaches employs equations relating drug content determination C at time t and temperature T. The identification procedures lead to the determination of only one initial drug content C0 for several different experiments. However, it is well known that because of experimental concentration variation or of intentional modification of the experimental schedule, there are as many initial drug contents as experiments. For these reasons, a method which takes into account batch effects is proposed to determine stability parameters and also all initial drug contents C(0j) where j is the index of experiment in one step. This method is more accurate from a statistical viewpoint and is suitable for data treatment in pharmaceutical industries where the initial drug content of each batch entering the stability program can be checked a posteriori. The application of this method is shown on real kinetic data from the hydrolysis of acetylsalicylic acid (ASA). Copyright (C) 1999 Elsevier Science B.V.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Determination of groundwater mercury (II) content using a disposable gold modified screen printed carbon electrode
No full textMercury (II) measurements were performed thanks to a newly developed electrochemical method using a disposable gold modified screen printed carbon electrode. The method has a wide dynamic range (1-100 μg/L), a good accuracy and a limit of detection in compliance with WHO standards. The application of the method to several groundwater samples made it possible to identify, for the first time, mercury content higher than the recommended WHO standard value in a gold mining activity area in the northern part of Burkina Faso. The accuracy of the assay was checked by ICP/MS.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Anaemia, zinc and vitamin A deficiency in 6-23 months old children from the rural district of Kongoussi (Burkina Faso).
No full textinfo:eu-repo/semantics/publishe
Contribution to the Detection of Poor Quality Sildenafil Drugs in Burkina Faso Using High-Performance Thin-Layer Chromatography
No full textIn substandard drugs enforcement, there is a need to develop reliable, fast, and inexpensive analytical methods. Due to its very characteristics, HPTLC offers opportunities for the development of methods that meet these requirements. This technique was used to develop and validate a method for the determination of sildenafil in pharmaceutical formulations from the licit and illicit supply chain in Burkina Faso. Taking into account optimization parameters such as measurement wavelength and mobile phase composition, the best elution quality is found at the maximum signals of spots on silica plates at 305 nm, using a mixture of dichloromethane-methanol mixture 9 : 1 (v/v) proportions. The method developed under these conditions was validated using the accuracy profile as a decision tool. The establishment of the response function curves allowed the choice of the polynomial function applied to the peak areas. This mathematical model provides a validity range between 0.4 and 0.6 mg/mL. The application of the developed and validated method to collected samples allowed the detection of two substandard drugs and confirmed the poor quality of drugs in the illicit market. More data using this approach in a variety of drug molecules could lead to the establishment of databases of counterfeit drugs in Burkina Faso
Stability parameter estimation at ambient temperature from studies at elevated temperatures
No full textSCOPUS: ar.jinfo:eu-repo/semantics/publishe
