Zone Electrophoresis Method For Determination Research Articles

Novel Eco-Friendly Stability Indicating Capillary Zone Electrophoresis Method for Determination of Aripiprazole in Tablet Dosage form: DoE Directed Optimization, Development and Method Validation

In this work, a novel environment-friendly stability indicating capillary zone electrophoresis (CZE) method has been developed and validated for assaying the aripiprazole (ARP) in tablet dosage form. The separation of ARP from its degradation products and internal standard was achieved using a fused silica capillary column (30.2 cm x 75 μm ID), a background electrolyte containing 6 mmol L−1 ammonium formate buffer (pH 3) with 5% methanol under a potential of 15 kV and detection at 214 nm. The stability indicating ability of the method was investigated by analyzing ARP after being subjected to acidic, alkaline, thermal, photolytic, and oxidative stress conditions, according to ICH guidelines. Design of experiments was used during forced degradation and method optimization. Oxidation was the main degradation pathway among those evaluated. The drug was separated from its oxidative degradation products in less than 4 min. CZE method was linear between 60 – 140 μg mL−1, R2 = 0.9980, precise (intra-day 0.88% and inter-day 1.30%). The average recovery was 100.93 ± 0.77%. This is the first method in the literature for quantification of ARP in the presence of its related degradation products with high separation efficiency, low operation cost and minimum solvent consumption. This method could be helpful in the routine quality control analysis in the pharmaceutical industries with least harmful effect on the environment. CZE is considered an eco-friendly alternative of conventionally HPLC methods.

Development, validation, and application of capillary zone electrophoresis method for determination of pyrimidine glucosides in seeds of Vicia faba L. var. minor.

Consumption of fava beans seeds can be harmful to both humans and animals due to the presence of pyrimidine glucosides: vicine and convicine. Therefore, seeds, feed supplements, and protein extracts derived from fava beans should be monitored for the contents of pyrimidine derivatives. The main objective of this work was the development and validation of an inexpensive, uncomplicated, quick, and robust method for the quantitation of vicine and convicine in seeds of fava beans. Plant material was extracted using a dual-phase extraction system to remove lipophilic contaminants and deactivate residual enzymes. Pyrimidine glucosides together with the internal standard: 5-bromouridine were separated using capillary zone electrophoresis (CZE) on an uncoated fused-silica capillary with alkaline, tetraborate-based electrolyte. Linearity, limits of detection and quantitation, precision, accuracy, recovery, and robustness of the method were investigated. The method was applied for quantitation of pyrimidine glucosides in seeds. Validation results suggest that the method is suitable for quantitation of pyrimidine glucosides, although it may not be sensitive enough for low-concentrated samples. Application of the method showed that seeds of the investigated variety of fava beans contain both vicine at 10-15 mg/g of dry weight and convicine at 3-5 mg/g of dry weight. Developed and validated CZE-ultraviolet (UV) method is suitable for analysis of pyrimidine glucosides in seeds of Vicia faba L. var. minor. It can be used as an inexpensive, greener alternative to more advanced methods while providing equally reliable and accurate results.

Development and validation of a sub-minute capillary zone electrophoresis method for determination of nitrate and nitrite in baby foods

This paper proposes an innovative sub-minute capillary zone electrophoresis method and a simple sample preparation procedure for simultaneous nitrate and nitrite determination. The novelty of the method is the simplicity of execution and the capacity to separate the analytes in less than 0.5 min. The BGE is composed of 10 mmol L(-1) perchloric acid and 40 mmol L(-1) β-alanine at pH 3.96. Thiocyanate was used as an internal standard. The method was validated following the Eurachem guidelines and applied to the analysis of 14 baby food samples. Of these samples, one had nitrate levels above that permitted by Brazilian legislation (250 mg kg(-1)) and for all samples the nitrite concentrations were under the limit of quantification. The good analytical performance verified for this method indicates that it is suitable for implementation in food laboratories for the routine determination of nitrate and nitrite as an alternative to the official method provided by the AOAC.

Development of a Capillary Zone Electrophoresis Method for Determination of Mebendazole and Levamisole Hydrochloride in a Combined Tablet and a Comparison with a LC Method

The separation and determination of mebendazole (MEB) and levamisole hydrochloride (LH) from a combination tablet by capillary zone electrophoresis (CZE) was developed and validated. The separation was performed in a 60 cm (50.5 cm to detection window) x 75 microm internal diameter fused silica capillary using a background electrolyte of NaH2PO4 (20 mM/L, pH 3.0 ) at 25 kV. Good separation was obtained in less than 8 min. The LOQ values for LH and MEB were 1.43 and 2.50 microg/mL, respectively; calibration curves were linear from 10 to 500 microg/mL with r2 > 0.999. Mean recoveries of the analytes were greater than 96%. In addition, a comparison with the LC method described in the 2010 Chinese Pharmacopoeia demonstrated that the developed CZE method was equally comparable with regard to linearity, sensitivity, precision, and accuracy, but the analysis time and reagent consumption were decreased. The CZE method is an effective and lower-cost alternative to the LC method.

Development and validation of a simple and rapid capillary zone electrophoresis method for determination of nnrti nevirapine in pharmaceutical formulations

A simple and fast capillary zone electrophoresis (CZE) method has been developed and validated for quantification of a non-nucleoside reverse transcriptase inhibitor (NNRTI) nevirapine, in pharmaceuticals. The analysis was optimized using 10 mmol L-1 sodium phosphate buffer pH 2.5, +25 kV applied voltage, hydrodynamic injection 0.5 psi for 5 s and direct UV detection at 200 µm. Diazepam (50.0 µg mL-1) was used as internal standard. Under these conditions, nevirapine was analyzed in approximately less than 2.5 min. The analytical curve presented a coefficient of correlation of 0.9994. Limits of detection and quantification were 1.4 µg mL-1 and 4.3 µg mL-1, respectively. Intra- and inter-day precision expressed as relative standard deviations were 1.4% and 1.3%, respectively and the mean recovery was 100.81%. The active pharmaceutical ingredient was subjected to hydrolysis (acid, basic and neutral) and oxidative stress conditions. No interference of degradation products and tablet excipients were observed. This method showed to be rapid, simple, precise, accurate and economical for determination of nevirapine in pharmaceuticals and it is suitable for routine quality control analysis since CE offers benefits in terms of quicker method development and significantly reduced operating costs.

Capillary Zone Electrophoresis method for determination of (+)-S clopidogrel carboxylic acid metabolite in human plasma and urine designed for biopharmaceutic studies

Fast and reproducible Capillary Zone Electrophoresis (CZE) method for the quantification of (+)-S clopidogrel carboxylic acid metabolite in human fluids was elaborated for the first time. Optimal buffer and CZE conditions were established to obtain the complete separation of clopidogrel, its metabolite and piroxicam (internal standard), during one analytical run. Finally, resolution of the analytes was obtained in an uncoated silica capillary filled with a phosphate buffer of pH 2.5. The analytes were isolated from plasma and urine samples using solid phase extraction (SPE). Validation of the CZE method was carried out. The calibration curve of clopidogrel was linear in the range of 0.5–10.0 mg/L in plasma and urine, whereas for (+)-S carboxylic acid metabolite linearity was confirmed in the range of 0.25–20.0 mg/L in plasma and 0.25–10.0 mg/L in urine. Intra- and inter-day precision and accuracy were repeatable. LOD and LOQ were also estimated. SPE recovery of the analytes from plasma and urine was comparable and greater than 80%. The validated method was successfully applied in pharmacokinetic investigations of (+)-S carboxylic acid metabolite of clopidogrel following the oral administration of clopidogrel to patients prior to percutaneous coronary intervention.

Development and validation of a rapid capillary zone electrophoresis method for the determination of aconite alkaloids in aconite roots

Aconites, with aconite alkaloids as the major therapeutic and toxic components, are used for the treatment of analgesic, antirheumatic and neurological symptoms. Quantification of the aconite alkaloids is important for the quality control of aconite-containing drugs. To establish a validated capillary zone electrophoresis (CZE) method for the simultaneous determination of six major alkaloids, namely aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine and benzoylhypaconine, in crude and processed aconite roots. The CZE method was optimised and validated using a stability-indicating method. The optimised running buffer was a mixture of 200 mm Tris, 150 mm perchloric acid and 40% 1,4-dioxane (pH 7.8) with the capillary thermostated at 25 degrees C. Using the optimised method, six aconite alkaloids were well separated. The established method showed good precision, accuracy and recovery. Contents of these alkaloids in crude and processed aconites were determined and it was observed that the levels of individual alkaloids varied between samples. The developed CZE method was reliable for the quality control of aconites contained in herbal medicines. The method could also be used as an approach for toxicological studies.

Capillary zone electrophoresis method for determination of bitter (α- and β-) acids in hop (Humulus lupulus L.) cone extracts

Humulus lupulus (H. lupulus), more commonly known as hop, is a member of the Cannabaceae family with male and female flowers on separate plants. It is native in Europe including Lithuania, Asia and North America. Hop has been recognized as a medicinal plant for centuries, nevertheless different medicinal activities of hop are currently investigated and discovered. An important class of hop compounds is the hop acids, which are classified as alpha-acids and beta-acids. Different varieties of hops vary in amount and composition of hop acids. Simple capillary zone electrophoresis method has been optimized and applied for the analysis of hop acids in hop cone extracts. With this method the analysis takes ca. 10 min. Repeatability for migration times and peak areas expressed as relative standard deviation were up to 0.21% and 5.96%, respectively. Comparative results of capillary zone electrophoretic analysis of extracts of different hop varieties and conductometric titration, as a standard method for determination of alpha-acids, are presented. Both methods provide consistent results, however capillary zone electrophoresis is capable of separating co- form of humulones from other forms.

Analysis of underivatized gentamicin by capillary electrophoresis with UV detection

A selective and rapid capillary zone electrophoresis method for determination of the multicomponent aminoglycoside antibiotic gentamicin is described. Baseline separation of gentamicin C1, C1a, C2, C2a and C2b components was achieved with a background electrolyte containing 0.35 mM cetyl trimethylammonium bromide, 3% methanol and 90 mM sodium pyrophosphate (pH 7.4) and detected directly with UV detection without derivatization. Quantitative analysis was performed and illustrated the potential use of capillary electrophoresis for the identification and quantitation of gentamicin components, but the application of this method is limited to a gentamicin concentration range of 2–6 mg/ml.

Validation of a Capillary Zone Electrophoresis Method for Determination of Rimantadine Hydrochloride in Rimantadin100 Tablets and the Method Application to Dissolution Test Monitoring

A capillary zone electrophoretic method with indirect UV‐detection for determination of rimantadine, an antiviral drug against influenza A, in tablets was validated. Instrumental precision, the method precision, accuracy, calibration curve linearity, selectivity, robustness, and time stability of the sample and the standard were tested. The method was also applied to monitor dissolution tests of the tablets. The possibility of addition of an internal standard for improvement of the method precision was discussed.

Development and validation of a capillary zone electrophoretic method for the determination of atenolol in presence of its related substances in bulk and tablet dosage form

The development of a capillary zone electrophoresis method for determination of the drug atenolol in the presence of its related substances in bulk and in a tablet dosage form is described. The method was fully validated in terms of repeatability (RSDs for migration time and peak area of atenolol at 0.05 mg ml −1 were 0.25% and 0.52%, {ce:inline-formula}n = 10{/ce:inline-formula}, respectively), reproducibility (RSD of peak area 0.84%, {ce:inline-formula}n = 5{/ce:inline-formula}), linearity at two ranges of atenolol concentration, limits of detection and quantitation, ruggedness and robustness. The method was applied to the determination of the drug in a commercial tablet preparation (recovery 99.4%, m/m). The method proved to be fast and reliable for the quantitative analysis of atenolol in the presence of its related substances in bulk and pharmaceutical forms.