In order to combat the counterfeiting of drugs, adapted HPLC analytical USP methods were applied to evaluate the quality of the amoxicillin (with or without potassium clavulanate) powder for suspension sold in some Co...In order to combat the counterfeiting of drugs, adapted HPLC analytical USP methods were applied to evaluate the quality of the amoxicillin (with or without potassium clavulanate) powder for suspension sold in some Congolese markets. The adaptation has been done by modifying the column dimensions and adjusting the flow rate. According to the intended deployment of these methods in Democratic Republic of Congo (DRC), 3 factors (analyst, day and equipment) were involved in the validation step while applying the classic total error measurement approach with an accuracy profile as decision tool. Since adequate results were obtained in terms of selectivity, precision, trueness and accuracy (tolerance limits of life expectancy: ?6.0% and 3.8%) for levels of interest concentration, the methods have been considered for routine use on several samples from different provenances and collected in 4 major DRC cities. Out of 278 samples collected, 200 were eligible for analysis from which 28% were found under standards with several figures: pH failure, out of specification for amoxicillin content, absence of potassium clavulanate, physical modifications of the powders. As evidenced by these findings, medicines of low-quality continue to be a major public health problem requiring appropriate action to effectively address this problem.展开更多
Liquid chromatographic methods in isocratic mode for the analysis of poor quality medicines are privileged due to their simplicity and facility in methods development. They are generally fast;do not need to be re-equi...Liquid chromatographic methods in isocratic mode for the analysis of poor quality medicines are privileged due to their simplicity and facility in methods development. They are generally fast;do not need to be re-equilibrated between sample injections;have larger flexibility with acceptable changes on different column dimensions;and are applicable to LC systems equipped with simple or high developed pumps. In this study, we focused on developing simple isocratic methods using classical mobile phase composed by methanol and ammonium formate buffer for the analysis of most common antimalarial medicines marketed in malaria endemic countries and susceptible of being counterfeit/falsified, substandard and degraded. The selected medicines were quinine and related cinchona alkaloids in tablets and injectable forms;artemether/lumefantrine tablets;and artemisinin compounds (arteether, artemether, and artesunate) in injectable forms. The current methods were developed thanks to simple methodological approach consisting in sequential isocratic runs through adjustment or adaptation of existing methods to obtain optimal analytical conditions without complex design of experiments that might be long and costly. Then, the new methods presented shorter analysis time;allowed increase of sample analysis throughput;and obviously consumed little mobile phase solvents on classical analytical columns: 50 - 250 mm of length (L), 4.6 mm of internal diameter (I.D.), and 3.5 - 5.0 μm of particle size (dp).展开更多
As serious but neglected public health problems, poor quality medicines, i.e. for antimalarial medicines, urged to be fought. One of the approaches is to consider the analytical chemistry and separative techniques. In...As serious but neglected public health problems, poor quality medicines, i.e. for antimalarial medicines, urged to be fought. One of the approaches is to consider the analytical chemistry and separative techniques. In this study, a generic liquid chromatographic method was firstly developed for the purpose of screening 8 antimalarial active ingredients, namely amodiaquine (AQ), piperaquine (PPQ), sulfalene (SL), pyrimethamine (PM), lumefantrine (LF), artesunate (AS), artemether (AM) and dihydroartemisinine (DHA) by applying DoE/DS optimization strategy. Since the method was not totally satisfying in terms of peak separation, further experiments were undergone applying the same development strategy while splitting the 8 ingredients into five groups. Excellent prediction was observed prior to correlation between retention times of predicted and observed separation conditions. Then, a successful geometric transfer was realized to reduce the analysis time focusing on the simultaneous quantification of two WHO’s recommended ACTs in anti-malarial fixed-dose combination (AM-LF and AS-AQ) in tablets. The optimal separation was achieved using an isocratic elution of methanol-ammonium formate buffer (pH 2.8;10 mM) (82.5:17.5, v/v) at 0.6 ml/min through a C18 column (100 mm × 3.5 mm, 3.5 μm) thermostated at 25℃. After a successful validation stage based on the total error approach, the method was applied to determine the content of AM/LF or AS/AQ in seven brands of antimalarial tablets currently marketed in West, Central and East Africa. Satisfying results were obtained compared to the claimed contents.展开更多
Nowadays, the circulation of poor quality medicines is becoming an alarming worldwide phenomenon with serious public health and socio-economic concerns. The situation is particularly critical in developing countries w...Nowadays, the circulation of poor quality medicines is becoming an alarming worldwide phenomenon with serious public health and socio-economic concerns. The situation is particularly critical in developing countries where drug quality assurance and regulatory systems for drug manufacturing, importation, distribution and sales are weak. A sustained vigilance on poor quality medicines that regroup counterfeit/falsified, substandard and degraded medicines is therefore required to ensure patient safety and genuine medicines integrity. A case situation is illustrated including a strategic approach and analytical tools that were found useful to detect poor quality medicines, identify unknown components, and timely alerts for appropriate measures against the spread of those harmful products. Several suspected medicines randomly sampled in several strategic Rwandan areas were firstly check-controlled by means of visual inspection and then applying several analytical techniques from simple to more complex ones. The following medicines were studied: quinine sulfate tablets, artemisinin-based combination tablets, and artesunate powders for injection. Taking into account the pharmaceutical forms and the chemical characteristics, the following tests were applied: uniformity of mass, friability, disintegration, fluorescence, identification and assay. They were followed by more complex analytical techniques that allowed more comprehension of abnormal findings among which the presence of a wrong active pharmaceutical ingredient in quinine sulfate tablets which is mainly discussed in this paper to illustrate a strategic approach and various analytical tools that can be used in detecting and identifying unknown component in poor quality medicines.展开更多
Even though Rwanda lies within a region that has a high prevalence of schistosomiasis and soil-transmitted helminth(STH)infections,epidemiological information regarding these infections in the country remains scarce.T...Even though Rwanda lies within a region that has a high prevalence of schistosomiasis and soil-transmitted helminth(STH)infections,epidemiological information regarding these infections in the country remains scarce.The present review attempts to compile the available data on schistosomiasis and STHs,from 1940 to 2014,to provide an insight on the epidemiological profile of these infections.This information will,in turn,support the design and implementation of sustainable control measures.The available records indicate that only Schistosoma mansoni and all the major species of STHs are endemic in Rwanda.In 2008,the national prevalence of S.mansoni was reported to be 2.7%,ranging from 0 to 69.5%,and that of STH infections was 65.8%(diagnosed using the Kato-Katz technique).The prevalence of these infections varies from one district to another,with schoolchildren remaining a highly affected group.The main control approach is mass drug administration using albendazole and praziquantel,mostly targeting school-aged children in school environments.In 2008,adult individuals living in areas with a prevalence of S.mansoni≥30%were also included in the mass drug administration programme.However,despite Rwanda achieving an almost 100%coverage of this programme in 2008-2010,the transmission of S.mansoni and STHs continues to take place,as illustrated by the most recent surveys.If Rwanda is to achieve sustainable control and elimination of schistosomiasis and STHs,there is a need to revise the country’s control strategy and adopt an integrated control approach that involves a combination of measures.展开更多
文摘In order to combat the counterfeiting of drugs, adapted HPLC analytical USP methods were applied to evaluate the quality of the amoxicillin (with or without potassium clavulanate) powder for suspension sold in some Congolese markets. The adaptation has been done by modifying the column dimensions and adjusting the flow rate. According to the intended deployment of these methods in Democratic Republic of Congo (DRC), 3 factors (analyst, day and equipment) were involved in the validation step while applying the classic total error measurement approach with an accuracy profile as decision tool. Since adequate results were obtained in terms of selectivity, precision, trueness and accuracy (tolerance limits of life expectancy: ?6.0% and 3.8%) for levels of interest concentration, the methods have been considered for routine use on several samples from different provenances and collected in 4 major DRC cities. Out of 278 samples collected, 200 were eligible for analysis from which 28% were found under standards with several figures: pH failure, out of specification for amoxicillin content, absence of potassium clavulanate, physical modifications of the powders. As evidenced by these findings, medicines of low-quality continue to be a major public health problem requiring appropriate action to effectively address this problem.
文摘Liquid chromatographic methods in isocratic mode for the analysis of poor quality medicines are privileged due to their simplicity and facility in methods development. They are generally fast;do not need to be re-equilibrated between sample injections;have larger flexibility with acceptable changes on different column dimensions;and are applicable to LC systems equipped with simple or high developed pumps. In this study, we focused on developing simple isocratic methods using classical mobile phase composed by methanol and ammonium formate buffer for the analysis of most common antimalarial medicines marketed in malaria endemic countries and susceptible of being counterfeit/falsified, substandard and degraded. The selected medicines were quinine and related cinchona alkaloids in tablets and injectable forms;artemether/lumefantrine tablets;and artemisinin compounds (arteether, artemether, and artesunate) in injectable forms. The current methods were developed thanks to simple methodological approach consisting in sequential isocratic runs through adjustment or adaptation of existing methods to obtain optimal analytical conditions without complex design of experiments that might be long and costly. Then, the new methods presented shorter analysis time;allowed increase of sample analysis throughput;and obviously consumed little mobile phase solvents on classical analytical columns: 50 - 250 mm of length (L), 4.6 mm of internal diameter (I.D.), and 3.5 - 5.0 μm of particle size (dp).
文摘As serious but neglected public health problems, poor quality medicines, i.e. for antimalarial medicines, urged to be fought. One of the approaches is to consider the analytical chemistry and separative techniques. In this study, a generic liquid chromatographic method was firstly developed for the purpose of screening 8 antimalarial active ingredients, namely amodiaquine (AQ), piperaquine (PPQ), sulfalene (SL), pyrimethamine (PM), lumefantrine (LF), artesunate (AS), artemether (AM) and dihydroartemisinine (DHA) by applying DoE/DS optimization strategy. Since the method was not totally satisfying in terms of peak separation, further experiments were undergone applying the same development strategy while splitting the 8 ingredients into five groups. Excellent prediction was observed prior to correlation between retention times of predicted and observed separation conditions. Then, a successful geometric transfer was realized to reduce the analysis time focusing on the simultaneous quantification of two WHO’s recommended ACTs in anti-malarial fixed-dose combination (AM-LF and AS-AQ) in tablets. The optimal separation was achieved using an isocratic elution of methanol-ammonium formate buffer (pH 2.8;10 mM) (82.5:17.5, v/v) at 0.6 ml/min through a C18 column (100 mm × 3.5 mm, 3.5 μm) thermostated at 25℃. After a successful validation stage based on the total error approach, the method was applied to determine the content of AM/LF or AS/AQ in seven brands of antimalarial tablets currently marketed in West, Central and East Africa. Satisfying results were obtained compared to the claimed contents.
文摘Nowadays, the circulation of poor quality medicines is becoming an alarming worldwide phenomenon with serious public health and socio-economic concerns. The situation is particularly critical in developing countries where drug quality assurance and regulatory systems for drug manufacturing, importation, distribution and sales are weak. A sustained vigilance on poor quality medicines that regroup counterfeit/falsified, substandard and degraded medicines is therefore required to ensure patient safety and genuine medicines integrity. A case situation is illustrated including a strategic approach and analytical tools that were found useful to detect poor quality medicines, identify unknown components, and timely alerts for appropriate measures against the spread of those harmful products. Several suspected medicines randomly sampled in several strategic Rwandan areas were firstly check-controlled by means of visual inspection and then applying several analytical techniques from simple to more complex ones. The following medicines were studied: quinine sulfate tablets, artemisinin-based combination tablets, and artesunate powders for injection. Taking into account the pharmaceutical forms and the chemical characteristics, the following tests were applied: uniformity of mass, friability, disintegration, fluorescence, identification and assay. They were followed by more complex analytical techniques that allowed more comprehension of abnormal findings among which the presence of a wrong active pharmaceutical ingredient in quinine sulfate tablets which is mainly discussed in this paper to illustrate a strategic approach and various analytical tools that can be used in detecting and identifying unknown component in poor quality medicines.
文摘Even though Rwanda lies within a region that has a high prevalence of schistosomiasis and soil-transmitted helminth(STH)infections,epidemiological information regarding these infections in the country remains scarce.The present review attempts to compile the available data on schistosomiasis and STHs,from 1940 to 2014,to provide an insight on the epidemiological profile of these infections.This information will,in turn,support the design and implementation of sustainable control measures.The available records indicate that only Schistosoma mansoni and all the major species of STHs are endemic in Rwanda.In 2008,the national prevalence of S.mansoni was reported to be 2.7%,ranging from 0 to 69.5%,and that of STH infections was 65.8%(diagnosed using the Kato-Katz technique).The prevalence of these infections varies from one district to another,with schoolchildren remaining a highly affected group.The main control approach is mass drug administration using albendazole and praziquantel,mostly targeting school-aged children in school environments.In 2008,adult individuals living in areas with a prevalence of S.mansoni≥30%were also included in the mass drug administration programme.However,despite Rwanda achieving an almost 100%coverage of this programme in 2008-2010,the transmission of S.mansoni and STHs continues to take place,as illustrated by the most recent surveys.If Rwanda is to achieve sustainable control and elimination of schistosomiasis and STHs,there is a need to revise the country’s control strategy and adopt an integrated control approach that involves a combination of measures.
