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See detailComparing the qualitative performances of handheld NIR and Raman spectrophotometers for the detection of falsified pharmaceutical products
Ciza Hamuli, Patient ULiege; Sacre, Pierre-Yves ULiege; Waffo Tchounga, Christelle ULiege et al

in Talanta (2019), 202

Over the last decade, the growth of the global pharmaceutical market has led to an overall increase of substandard and falsified drugs especially on the African market (or emerging countries). Recently ... [more ▼]

Over the last decade, the growth of the global pharmaceutical market has led to an overall increase of substandard and falsified drugs especially on the African market (or emerging countries). Recently, several methods using handheld/portable vibrational spectroscopy have been developed for rapid and on-field drug analysis. The objective of this work was evaluate the performances of various NIR and Raman handheld spectrophotometers in specific brand identification of medicines through their primary packaging. Three groups of drug samples (artemether-lumefantrine, paracetamol, and ibuprofen) were used in tablet or capsule forms. In order to perform a critical comparison, the analytical performances of the two analytical systems was compared statistically using three methods: hierarchical clustering algorithm (HCA), data-driven soft independent modeling of class analogy (DD-SIMCA) and hit quality index (HQI). The overall results show good detection abilities for NIR systems compared to Raman systems based on Matthews’s correlation coefficients, generally close to one. Raman systems are less sensitive to the physical state of the samples than the NIR systems, it also suffers of the auto-fluorescence phenomenon and the signal of highly dosed active pharmaceutical ingredient (e.g. paracetamol or lumefantrine) may mask the signal of low-dosed and weaker Raman active compounds (e.g. artemether). Hence, Raman systems are less effective for specific product identification purposes but are interesting in the context of falsification because they allow a visual interpretation of the spectral signature (presence or absence of API). [less ▲]

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See detailComparing the qualitative performances of handheld NIR and Raman spectrometers for the analysis of falsified pharmaceutical products.
Ciza Hamuli, Patient ULiege; Waffo Tchounga, Christelle ULiege; Coic, Laureen ULiege et al

Poster (2018, September)

The last decade has seen a significant growth of the pharmaceutical market of emerging countries to the point that it has induced many falsifications. Research activities have followed this growth but not ... [more ▼]

The last decade has seen a significant growth of the pharmaceutical market of emerging countries to the point that it has induced many falsifications. Research activities have followed this growth but not proportionately. Recently, several chemical analysis methods for the detection of counterfeit or falsified drugs have been developed using spectroscopic techniques. In this study, different spectrometers were used to collect near-infrared (NIR) and Raman spectral data sets of selected drugs to help improve existing methods. The objective of this work was to evaluate the qualitative performances of the NIR and Raman spectrometers; two benchtop equipment (NIR and Raman) and four handheld ones (three Raman and one NIR) were used. In particular, we made a critical comparison in the evaluation of the accuracy of the prediction. The predictive ability of the different equipments was compared statistically using chemometrics: clustering algorithm, soft modeling (DD-SIMCA) and hard modeling (PLS-DA). All these chemometric strategies were applied on each equipment. Clustering approaches, DD-SIMCA and PLSDA enabled us to compare the qualitative performances of handheld NIR and Raman equipment and to make a critical analysis of their use in the field of the detection of falsified drugs. [less ▲]

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See detailEtude comparative des profils de dissolution in vitro de quinine sulfate générique et princeps en utilisant la Chromatographie Liquide Haute Performance
Mbinze Kindenge, Jérémie ULiege; Diallo, Tediane; Yemoa, Loconon ULiege et al

in Médecine d'Afrique Noire (2017), 64

Introduction : La quinine est une molécule préconisée pour le traitement du paludisme dans les régions où les souches de P. falciparum sont polyrésistantes. Face à l’importante utilisation de ses ... [more ▼]

Introduction : La quinine est une molécule préconisée pour le traitement du paludisme dans les régions où les souches de P. falciparum sont polyrésistantes. Face à l’importante utilisation de ses médicaments génériques d’une part, et au fléau des médicaments de qualité inférieure d’autre part, il devient plus que nécessaire d’appuyer les données des tests physico-chimiques par celles de dissolution in vitro dont l’évaluation et la comparaison des cinétiques permettra de prédire le comportement in vivo du principe actif et par conséquent l’efficacité du médicament générique. L’objectif de la présente étude est de réaliser une étude comparative de la cinétique de dissolution d’un princeps et d’un générique à base de quinine comprimé 300 mg commercialisés à Kinshasa. Matériels et méthodes : L’étude a été réalisée en utilisant trois milieux de pH différents (1,2 - 4,5 - 6,8) tels que recommandés par l’Agence Européenne de Médicament et en se servant d’un appareil de dissolution, tandis que l’équipement de chromatographie liquide à haute performance couplée à un détecteur à barrette de diodes a été utilisé pour la quantification. La méthode statistique fit factor a été appliquée pour comparer les résultats de dosage de la quinine dans les trois milieux tout en ayant évalué le biais à différents temps de dissolution. Résultats : Les différents échantillons de médicaments générique et princeps ont été conformes quant à l’identification et au dosage de la quinine, par contre leurs cinétiques de dissolution étaient non similaires. Discussion : Ceci pourrait avoir une influence sur l’efficacité du produit générique et la sécurité des consommateurs, dénotant l’importance d’examiner les profils de dissolution des génériques avant toute autorisation de mise sur le marché plus particulièrement dans les pays en voie de développement. [less ▲]

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See detailINVESTIGATION DE LA QUALITE D’ANTIBIOTIQUES A BASE D'AMOXICILLINE DANS LE CADRE DE LA SURVEILLANCE DU MARCHE OFFICIEL ET PERIPHERIQUE DE QUELQUES VILLES DE LA R.D. CONGO
Kalenda Tshilombo, Nicodème ULiege; Ciza Hamuli, Patient ULiege; Mavungu Landu, Don Jethro ULiege et al

Poster (2017, March)

Drug counterfeiting is a sad and worrisome reality, especially in developing countries where quality control is not effective and sometimes not existing at all despite political will of governments. The ... [more ▼]

Drug counterfeiting is a sad and worrisome reality, especially in developing countries where quality control is not effective and sometimes not existing at all despite political will of governments. The consequences are harmful in particular for substandard medicines that pose more threats to populations in those countries due to their direct negative impact on patients such as failure of medical treatment including development of drug resistance and even death. Socio-economic consequences and negative reputation concerning the pharmaceutical industry are also observed. Unfortunately accurate detailed data on such medicines are not easy to obtain. Most of the time available data are often estimated from case reports or studies carried out in a specific area and during a defined period.Health authorities’ in the Democratic Republic of Congo are trying to identify this scourge by set up several strategies to fight against. One of them is built on the best knowledge of drugs from several horizons through the assessment of their quality to allow appropriate measurement. In this context, we have focused our study towards amoxicillin alone and/or combined with potassium clavulanate since it is one the very used medicines in pediatric medications. The formulations are powder for suspension. Two analytical methods were developed based on the USP monography, applying isocratic liquid chromatography. Prior to their application in routine, we evaluated the suitability of these methods through validation applying the accuracy profile of total error. Since it was planned to transfer the methods to DRC, several operating factors were taken into account namely operator, day and equipment. Interesting results were obtained in terms of trueness (relative biases below than 2.3%), precision (RSD of Intermediate precision below 2.8%), accuracy (beta-expectation tolerance intervals between -6.0% and 3.8%) for the concentration levels of interest. The latter were able to allow monitoring the quality of the two active ingredients here above in the 65 samples from Congolese market. They were collected in Kinshasa, Lubumbashi, Matadi and Kolwezi at official and non-official medicines distributors, in peripheral area. The dramatic results obtained confirm that substandard and counterfeit medicines remain a crucial problem on public health in low-income countries. Appropriate measures are really needed to set up the drug quality improvement. [less ▲]

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