A high-performance liquid chromatography (HPLC) method has been developed and validated for the determination of dexamethasone palmitate (DXP) in bronchoalveolar fluid lavage samples (BALF). DXP in rat BALFs containin...A high-performance liquid chromatography (HPLC) method has been developed and validated for the determination of dexamethasone palmitate (DXP) in bronchoalveolar fluid lavage samples (BALF). DXP in rat BALFs containing the internal standard (IS), testosterone decanoate (TD), was extracted using a mixture of chloroform and methanol (9:1, v/v). Extracts were then centrifuged, dried and dissolved in acetonitrile. A chromatographic separation based on an isocratic elution was done using acetonitrile and water (85:15, v/v) as a mobile phase at a flow rate of 1.2 mL/min. The graph of the developed method was linear within the tested calibration range of 0.5 - 40 μg/mL. The overall extraction recovery of DXP from BALF samples was 84.3% ± 1.6%. The accuracy (relative error) and precision (coefficient of variation) values were within the pre-defined limits of ≤15% at all concentrations. This methodology has been applied to determine levels of DXP in BALF samples collected from rats treated with DXP large porous particles. The measured concentrations were successfully evaluated using a non-compartment pharmacokinetic model. Since the developed method requires only a microvolume (100 μL) of BALF sample for analysis, it is therefore particularly suitable for the evaluation of drug biodistribution in lung.展开更多
WHO strategy on traditional medicine is based on security and quality of phytomedicine. Commonly adulterated affecting mostly metabolic and sexual dysfunction drugs. Control quality of those phytomedicines requires de...WHO strategy on traditional medicine is based on security and quality of phytomedicine. Commonly adulterated affecting mostly metabolic and sexual dysfunction drugs. Control quality of those phytomedicines requires development of strategy and techniques applicable to them. Among the techniques, Reverse Phase Liquid Chromatography is the most used and has been developed in these studies to assess a protocol to characterize Gardenia aqualla leaves extract. The method consists in determining chromatographic conditions using organic and pH gradient models based on water and acetonitrile combined with pH modifiers made up of formic acid (AF) and ammonium hydroxide (NH<sub>3</sub>). Results show that extracts contain mainly acidic compounds quickly eluted by NH<sub>3</sub> and more retained by AF. Optimal pH range for separation is 3 - 7 corresponding to 1.59 mM of NH<sub>3</sub> and 6.55 mM of AF. In these conditions, elution of many polar compounds could be effective using a C18 based-deactivated column in a short period of time.展开更多
In order to provide the population with safe, effective and good quality medicines, the pharmaceutical industries, before releasing batches of their products into the pharmaceutical circuit, put in place internal dosa...In order to provide the population with safe, effective and good quality medicines, the pharmaceutical industries, before releasing batches of their products into the pharmaceutical circuit, put in place internal dosage methods to control the quality of these products. The present study consisted in optimizing a method for the simultaneous determination of Phloroglucinol (PHG) and Trimethylphloroglucinol (TPH) by high performance liquid chromatography (HPLC) routinely used in a pharmaceutical industry located in a township in Abidjan (Ivory Coast). The basic chromatographic conditions were those routinely used for the determination of these two molecules: mobile phase: acetonitrile/water (60/40), stationary phase (C18 BDS Hypersil 250 mm * 4.6 mm - 5 μm), detection wavelength (265 nm), flow rate, injection volume and run time configured at the equipment level were respectively 1 mL/min, 10 μL and 8 min. The method of preparation of the analytes (PHG and TPHG) was also applied by the pharmaceutical industry. The application of these different parameters at the equipment level made it possible to determine a chromatogram which highlights three chromatographic peaks with respective retention times (RT) of 0.773 min (unidentified compound), 2.275 min (PHG) and 7.269 min for an analysis time of 8 min with a better resolution of the peaks and baseline. The progressive optimization of different parameters such as the stationary phase (C18 YMC 150 mm * 4.6 mm - 3 μm), the proportion of the mobile phase: acetonitrile/water (80/20), the flow rate impelled by the pump (0.8 mL/min) and the modification of the analyte preparation mode (same amount of PHG and TPHG in a 50 mL volumetric flask) resulted in a final chromatogram that highlighted two chromatographic peaks at the respective RT of 2.391 min (PHG) and 3.735 min (TPHG) at a run time of 6 min. The chromatographic conditions that led to the final chromatogram can be used routinely by the pharmaceutical industry for the determination of several PHG and TPHG drug matrices after prior validation of the determination method.展开更多
文摘A high-performance liquid chromatography (HPLC) method has been developed and validated for the determination of dexamethasone palmitate (DXP) in bronchoalveolar fluid lavage samples (BALF). DXP in rat BALFs containing the internal standard (IS), testosterone decanoate (TD), was extracted using a mixture of chloroform and methanol (9:1, v/v). Extracts were then centrifuged, dried and dissolved in acetonitrile. A chromatographic separation based on an isocratic elution was done using acetonitrile and water (85:15, v/v) as a mobile phase at a flow rate of 1.2 mL/min. The graph of the developed method was linear within the tested calibration range of 0.5 - 40 μg/mL. The overall extraction recovery of DXP from BALF samples was 84.3% ± 1.6%. The accuracy (relative error) and precision (coefficient of variation) values were within the pre-defined limits of ≤15% at all concentrations. This methodology has been applied to determine levels of DXP in BALF samples collected from rats treated with DXP large porous particles. The measured concentrations were successfully evaluated using a non-compartment pharmacokinetic model. Since the developed method requires only a microvolume (100 μL) of BALF sample for analysis, it is therefore particularly suitable for the evaluation of drug biodistribution in lung.
文摘WHO strategy on traditional medicine is based on security and quality of phytomedicine. Commonly adulterated affecting mostly metabolic and sexual dysfunction drugs. Control quality of those phytomedicines requires development of strategy and techniques applicable to them. Among the techniques, Reverse Phase Liquid Chromatography is the most used and has been developed in these studies to assess a protocol to characterize Gardenia aqualla leaves extract. The method consists in determining chromatographic conditions using organic and pH gradient models based on water and acetonitrile combined with pH modifiers made up of formic acid (AF) and ammonium hydroxide (NH<sub>3</sub>). Results show that extracts contain mainly acidic compounds quickly eluted by NH<sub>3</sub> and more retained by AF. Optimal pH range for separation is 3 - 7 corresponding to 1.59 mM of NH<sub>3</sub> and 6.55 mM of AF. In these conditions, elution of many polar compounds could be effective using a C18 based-deactivated column in a short period of time.
文摘In order to provide the population with safe, effective and good quality medicines, the pharmaceutical industries, before releasing batches of their products into the pharmaceutical circuit, put in place internal dosage methods to control the quality of these products. The present study consisted in optimizing a method for the simultaneous determination of Phloroglucinol (PHG) and Trimethylphloroglucinol (TPH) by high performance liquid chromatography (HPLC) routinely used in a pharmaceutical industry located in a township in Abidjan (Ivory Coast). The basic chromatographic conditions were those routinely used for the determination of these two molecules: mobile phase: acetonitrile/water (60/40), stationary phase (C18 BDS Hypersil 250 mm * 4.6 mm - 5 μm), detection wavelength (265 nm), flow rate, injection volume and run time configured at the equipment level were respectively 1 mL/min, 10 μL and 8 min. The method of preparation of the analytes (PHG and TPHG) was also applied by the pharmaceutical industry. The application of these different parameters at the equipment level made it possible to determine a chromatogram which highlights three chromatographic peaks with respective retention times (RT) of 0.773 min (unidentified compound), 2.275 min (PHG) and 7.269 min for an analysis time of 8 min with a better resolution of the peaks and baseline. The progressive optimization of different parameters such as the stationary phase (C18 YMC 150 mm * 4.6 mm - 3 μm), the proportion of the mobile phase: acetonitrile/water (80/20), the flow rate impelled by the pump (0.8 mL/min) and the modification of the analyte preparation mode (same amount of PHG and TPHG in a 50 mL volumetric flask) resulted in a final chromatogram that highlighted two chromatographic peaks at the respective RT of 2.391 min (PHG) and 3.735 min (TPHG) at a run time of 6 min. The chromatographic conditions that led to the final chromatogram can be used routinely by the pharmaceutical industry for the determination of several PHG and TPHG drug matrices after prior validation of the determination method.
