Bosentan monohydrate (4-tert-butyl-N-[6-(2-hydroxyethoxy)-5-(2-methoxyphenoxy)-2-(pyrimidin-2-yl) pyrimidin-4-yl]benzene-1-sulfonamide monohydrate) is a dual endothelin receptor antagonist (ERA) applied in the treatment of pulmonary arterial hypertension. To achieve effective process control of the bosentan monohydrate synthesis, it was necessary to develop a selective and not highly time-consuming method for ultra-high performance liquid chromatography (UHPLC). The method is characterized by adequate sensitivity, reproducibility and selectivity for the determination of bosentan monohydrate and related compounds from all synthetic stages. The UHPLC separation was carried out by reversed phase chromatography on the Acquity BEH C18 column (100 mm × 2.1 mm, 1.7 µm) with a mobile phase composed of solvent A (0.1 %, v/v, acetic acid in water) and solvent B (methanol), in the gradient mode at the flow rate of 0.4 mL min−1. Limits of detection and quantification for the compounds were ≤0.1 µg mL−1 and 0.3 µg mL−1, respectively. The linearity for all related compounds was investigated as in the range for the active pharmaceutical ingredient (API) and as in the range for the in-process control. The developed method was validated according to the current guidelines, proving the suitability of the method for its intended purpose.
相似文献A stability-indicating ultra-high-performance liquid chromatography (UHPLC) method with a diode array detector was developed and validated for the determination of cis/trans isomers of perindopril l-arginine in bulk substance and pharmaceutical dosage form. The separation was achieved on a Poroshell 120 Hilic (4.6 × 150 mm, 2.7 µm) column using a mobile phase composed of acetonitrile–0.1 % formic acid (20:80 v/v) at a flow rate of 1 mL min−1. The injection volume was 5.0 µL and the wavelength of detection was controlled at 230 nm. The selectivity of the UHPLC-DAD method was confirmed by determining perindopril l-arginine in the presence of degradation products formed during acid–base hydrolysis and oxidation as well as degradation in the solid state, at an increased relative air humidity and in dry air. The method’s linearity was investigated in the ranges 0.40–1.40 µg mL−1 for isomer I and 0.40–2.40 µg mL−1 for isomer II of perindopril l-arginine. The UHPLC-DAD method met the precision and accuracy criteria for the determination of the isomers of perindopril l-arginine. The limits of detection and quantitation were 0.1503 and 0.4555 µg mL−1 for isomer I and 0.0356 and 0.1078 µg mL−1 for isomer II, respectively.
相似文献A precise and sensitive LC method for determination of enantiomeric purity of trelagliptin has been developed and validated. Pre-column derivatization was performed before separation. Baseline separation with a resolution factor >2.5 was accomplished within 10 min by use of a Chiralpak AD column (250 × 4.6 mm; particle size 5 µm) and n-hexane–2-propanol (90:10 v/v) as mobile phase at a flow rate of 1 mL min−1. Eluted analytes were monitored by UV detection at 260 nm. The effects of mobile phase composition and temperature on enantiomeric selectivity and on resolution of enantiomers were thoroughly investigated. Calibration curves were plotted within the concentration range 0.005–2 mg mL−1 (n = 12), and recoveries between 98.23 and 101.34 % were obtained, with relative standard deviation (RSD) <1.39 %. LOD and LOQ for the trelagliptin derivative were 1.51 and 5.03 µg mL−1; those for its enantiomer were 1.49 and 4.94 µg mL−1, respectively. The method was evaluated and validated by analysis of bulk samples of trelagliptin of different enantiomeric purity. It was demonstrated that the method was accurate, robust, and sensitive, and enabled practical analysis of real samples.
相似文献A RP-LC method is presented, which is sensitive and selective for the simultaneous determination of enalapril–lercanidipine and enalapril–nitrendipine binary mixtures in their pharmaceutical dosage forms. The analyte peaks were detected using the LC method with the mobile phase ratio of methanol: water (70:30 v/v, pH 3.0) and a 1.0 mL min−1 flow rate. The detection wavelength was selected at 210 nm using photo diode array detector and column temperature was optimized to 30 °C. Linearity was obtained at different concentration ranges for all working pharmaceutically active compounds between 0.5 and 25 μg mL−1. The proposed methods were extensively validated according to USP 27 requirements and ICH guidelines. The methods were applied to the analysis of pharmaceutical dosage forms containing binary mixtures of enalapril–lercanidipine and enalapril–nitrendipine. Moreover, the proposed methods were applied for the degradation studies of the selected compounds. Degradation studies were conducted using stress conditions such as UV light, acidic and alkaline hydrolysis, oxidation and heat in oven, to evaluate the ability of the separation of the response of standard compounds from their degradation products.
相似文献A reversed-phase high-performance liquid chromatographic method was developed for the simultaneous determination of sofosbuvir and ledipasvir in tablet dosage form. The analysis was performed on Luna analytical column 250 × 4.6 mm, 5 µm, octyl silica packing (Si–[CH2]7–CH3) C8, using ammonium acetate buffer solution pH 7.0 and acetonitrile 35:65 % v/v as mobile phase at flow rate of 0.7 mL min−1 for isocratic elution. Detection of sofosbuvir and ledipasvir was performed on a UV detector at 245 nm. The retention times of sofosbuvir and ledipasvir were 4.468 ± 0.013 min and 8.242 ± 0.012 min, respectively, and the total run time was 20 min. The method was validated according to the requirements of the United States Pharmacopeia (category I). The overall recovery of both analytes was 100 ± 1 %; the relative standard deviation for precision and intraday precision was less than 2.0 %. The method was linear with correlation coefficient (r) >0.9999, limits of detection 0.485 and 0.175 µg mL−1, and limits of quantification was 1.619 and 0.586 µg mL−1 for sofosbuvir and ledipasvir, respectively. The method was successfully applied to the assay and in vitro dissolution studies of sofosbuvir and ledipasvir in tablet dosage form.
相似文献High-performance liquid chromatography with tandem mass spectrometry has been used for rapid, specific, and sensitive analysis of busulfan in human plasma. Busulfan-d8 was used as internal standard. Analysis was performed on a C18 column (50 mm × 2.1 mm, 3.5-µm particles) with water–methanol 80:20 (v/v) as mobile phase at a flow-rate of 0.30 mL min−1. Detection was by tandem triple–quadrupole mass spectrometry with turbo ion-spray ionization. Linear calibration plots were obtained over the concentration range 1.096–1,096 ng mL−1. The assay is ideally suited to monitoring of busulfan and determination of its pharmacokinetic data.
相似文献A sensitive UHPLC-DAD method was developed for determination of diastereoisomers of cefuroxime axetil in bulk substance in amorphous and crystalline forms as well as in pharmaceutical preparations. Chromatographic separation was achieved on Kinetex C-18 (100 mm × 2.1 mm, 1.7 µm) column with mobile phase consisting of 0.1 % formic acid:methanol (88:12, v/v), at the flow rate of 0.7 mL min−1 and total run time of 3 min. The wavelength of the DAD detector was set at 278 nm. Inter-day precision (RSD) was less than 3 % and accuracy level ranged between 98.31 and 104.99 %. Degradation products of cefuroxime axetil in aqueous solutions and in the solid state were identified with a EIS-Q-MS mass spectrometer. The solubility of above-mentioned polymorphic forms of cefuroxime axetil in suitable solvents is a crucial factor during preparation of samples and is essential for chromatographic separation of its diastereoisomers.
相似文献A simple, suitable reverse phase liquid chromatographic method was developed for simultaneous determination of andrographolide (1) and dehydroandrographolide (2) in chicken plasma after orally administrating the ultra-fine powder of Andrographis paniculata. Plasma samples were extracted with ethyl acetate. Analysis of the extract was performed on a reversed-phase C18 column with gradient eluent composed of acetonitrile and 0.5% acetic acid. The flow rate was kept at 1 mL min−1 and the detection wavelength was set at 225 and 255 nm for 1 and 2, respectively. All calibration curves showed good linear regression (R ≥ 0.9991). The good precision and recoveries with intra-day and inter-day were 3.2–8.7% and 91.1–98.4%, respectively. The limit of detection was 0.016 µg mL−1 and the limit of quantitation was 0.040 µg mL−1 for the target analytes. This validated method has been successfully applied in the pharmacokinetics study of 1 and 2 after orally administrating the Andrographis paniculata ultra-fine powder to chicken.
相似文献A reversed-phase ion-pairing liquid chromatographic method was developed and validated for the assay of Fe(II) in ferrous bisglycinate (Fe-bis-gly) capsules using 4-(2-pyridylazo) resorcinol reagent. The analysis was carried out using a Gemini RP-18 (150 mm × 4.6 mm I.D., particle size 5 μm) analytical column; the mobile phase consisted of a mixture of acetonitrile–water (28:72 v/v) containing 1 mM tetrabutylammonium hydrogensulfate and 1% phosphate buffer (pH 8.0). The flow rate was 1.0 mL min−1 and the detection was achieved with a photodiode array (PDA) detector at 706 nm. The specificity of the method was proved using stress conditions and evaluated using a PDA detector. The data validation showed that the method is specific, fast, accurate, and reproducible for the determination of Fe-bis-gly in dosage form. The response was linear over a range of 1.0–2.6 μg mL−1 (r = 0.9999). The accuracy of the method ranged from 98.02 to 102.75%. The RSD values for intra- and inter-day precision studies were below 1.3 and 1.1%, respectively. There was no interference of the excipients on the determination of the active pharmaceutical ingredient.
相似文献A new method involving matrix solid-phase dispersion (MSPD) extraction and UPLC in conjunction with photodiode array detection was developed for the rapid and simple determination of Sudan dyes in chili powder. Separation of Sudan I, Sudan II, Sudan III, and Sudan IV was achieved within 2 min on the 1.7 μm Acquity UPLC BEH C18 column by using gradient elution with a mobile phase consisting of acetonitrile–water at a flow rate of 0.5 mL min−1. Optimization of MSPD extraction parameters, such as type of solid sorbent and elution solvent were carried out. Optimal conditions selected for MSPD extraction were 0.25 g of sample, 0.5 g of silica gel as solid sorbent, and 7 mL of acetonitrile–methanol (9:1, v/v) as eluting solvent. Limits of detection ranged between 0.25 and 0.30 mg kg−1 depending on the dye involved. All analytes provided average recoveries from spiked (at 1, 1.5, and 2 mg kg−1) chili powder samples ranging from 81 to 106%. The method was applied to the analysis of chili powder samples obtained from different countries.
相似文献An accurate, simple, reproducible, and sensitive liquid chromatographic method was developed and validated for the captopril determination in controlled release tablets. The analyses were performed at room temperature on a reversed-phase Phenomenex Luna C18 column (250 mm × 4.6 mm). The mobile phase was composed of water:methanol (45:55; v/v) pH 2.5, and it was eluted isocratically at a 1.0 mL min−1 flow rate. The method was validated in terms of specificity, linearity, quantification limit, detection limit, accuracy, precision and robustness. The response was linear in the range 0.3–1.5 mg mL−1 (r 2 = 0.9983). The relative standard deviation values for inter-and intra-day precision were 0.77% and 0.50%, respectively. Recoveries ranged between 97.7 and 99.1%. The method was successfully applied for the determination of captopril in the developed formulations.
相似文献A sensitive and rapid liquid chromatographic method was successfully developed and validated for the determination of sibutramine hydrochloride in bulk and capsules. Sibutramine in the presence of its degradation products was analyzed using UV detection at 225 nm. Chromatography was performed on a reversed-phase C8 (150 × 4.0 mm I.D., 5 μm) analytical column under isocratic conditions. The mobile phase was composed of acetonitrile:water (aqueous phase containing 0.3% triethylamine and pH adjusted to 7.0) (75:25, v/v) at a flow-rate of 1.1 mL min−1. No chromatographic interference was found during the analysis. Light was the stress condition which most contributed to sibutramine degradation. The method showed a linear response (r > 0.999) from 30 to 90 μg mL−1. The mean recovery for capsules was 101.2%. Inter-day assays showed relative standard deviations of 0.42 and 1.62% for bulk and capsules, respectively. The developed method is able to separate sibutramine from its major degradation products and it may be used in the quality control of this active pharmaceutical ingredient in both bulk and capsules.
相似文献A simple, rapid and robust enantioselective method was developed and validated for the quantitation of OTX015 enantiomers [(−)-OTX015 and (+)-OTX015] with ultrahigh-performance liquid chromatography (UHPLC) as per ICH guidelines. The active [(−)-OTX015] and inactive [(+)-OTX015] enantiomers were resolved on a Chiralpak-IA column using methanol consisting of 0.1 % diethyl amine at a flow rate of 1.0 mL min−1. The resolution between the enantiomers was found to be more than 3.7 in the optimized method. The developed method was extensively validated and proven to be robust. The calibration curve for (+)-OTX015 showed excellent linearity over the concentration range of 10–100 µg mL−1. The limit of detection and the limit on quantitation for (+)-OTX015 were 5 and 10 µg mL−1, respectively. The recovery for (+)-OTX015 ranged between 100.7 and 102.5 % in the bulk drug sample of (−)-OTX015. The proposed method was found to be suitable and accurate for quantitative determination of (+)-OTX015 in bulk drug.
相似文献A precise and sensitive LC method for the determination of repertaxin enantiomeric purity has been developed and validated. Baseline separation with a resolution higher than 2.0 was accomplished within 20 min using a Chiralpak AD-H column (250 × 4.6 mm; particle size 5 μm) and n-hexane:2-propanol (90:10 v/v) as mobile phase at a flow rate of 1 mL min−1. Eluted analytes were monitored by UV detection at 260 nm. The effects of mobile phase composition, temperature and flow rate on enantiomeric selectivity and on resolution of enantiomers were investigated. Calibration curves were plotted within the concentration range between 0.002 and 1.0 mg mL−1 (n = 3), and relative standard deviation (RSD) of the inter-batch assay and intra-batch assay was less than 1.27 and 1.16 %. LOD and LOQ for repertaxin were 0.65 and 2.19 μg mL−1; those for its enantiomer were 0.70 and 2.34 μg mL−1, respectively. The method was evaluated and validated by analysis of bulk samples of repertaxin of different enantiomeric purity. It was demonstrated that the method was accurate, robust, and sensitive, and enabled practical analysis of real samples.
相似文献Two chromatographic methods have been described for the simultaneous determination of metronidazole (MET) and spiramycin (SPY) in their mixtures. The first method was based on a high performance thin layer chromatographic (HPTLC) separation of the two drugs followed by densitometric measurements of their spots at 240 nm. The separation was carried out on Merck TLC aluminum sheets of silica gel 60 F254 using methanol: chloroform (9:1, v/v) as a mobile phase. Analysis data was used for the linear regression line in the range of 1.0–2.0 and 0.8–2.0 μg band−1 for MET and SPY, respectively. The second method was based on a reversed-phase liquid chromatographic separation of the cited drugs on a C-18 column (5 μm, 250 × 4.6 mm, i.d.). The mobile phase consisted of a mixture of phosphate buffer of pH 2.4 and acetonitrile (70:30, v/v). The separation was carried out at ambient temperature with a flow rate of 1.0 mL min−1. Quantitation was achieved with UV detection at 232 nm based on peak area with linear calibration curves at concentration ranges 0.4–50.0 and 0.5–50.0 μg mL−1 for MET and SPY, respectively. The proposed chromatographic methods were successfully applied to the determination of the investigated drugs in pharmaceutical preparations. Both methods were validated in compliance with ICH guidelines; in terms of linearity, accuracy, precision, robustness, limits of detection and quantitation and other aspects of analytical validation.
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