Rapid Capillary Zone Electrophoresis Research Articles

Determination of topiramate in human plasma by capillary electrophoresis with indirect UV detection

A rapid capillary zone electrophoresis method with indirect UV detection for the determination of topiramate in human plasma was developed and validated. The analyses were carried out with a background electrolyte composed of 10 mM sulfamethoxazole as chromophore in phosphate buffer (25 mM, pH 12.0); gabapentin was selected as the internal standard. Application of a voltage of +15 kV led to an analysis time shorter than 5 min; indirect UV detection was operated at 256 nm. Isolation of topiramate from plasma was accomplished by a carefully implemented solid-phase extraction procedure on C18 cartridges. The method provided a linear response over the concentration range of 2–60 μg of topiramate per mL of plasma. The limit of detection (LOD) was 0.8 μg mL −1 and the limit of quantitation (LOQ) was 2.0 μg mL −1. Precision, expressed as relative standard deviation, was always lower than 7.3%, extraction yields were always greater than 92%. The results obtained analysing plasma samples from epileptic patients undergoing therapy with topiramate were satisfactory in terms of precision and selectivity.

CZE separation of nitrogenous drugs in cationic form

A rapid and efficient capillary zone electrophoresis method was developed for Quality Control analysis of pharmaceutical preparations containing antihistamines, decongestants and anticholinergic remedies: chlorpheniramine, diphenhydramine, ephedrine, isopropamide, pheniramine. These analytes were separated in cationic form optimizing the experimental conditions in 60 mM tetraborate buffer pH = 9.2 as a BGE (Background Electrolyte) on a Beckman P/ACE System MDQ instrument. The effective capillary length was 48 cm, I.D. = 75 μm, the applied voltage 15 kV, and the temperature 25 °C. Detection was performed by a DAD (Diode Array Detector) at 210 nm. Separation time was less than 8 min. After experimental conditions optimization, the proposed method was validated. Precision of migration time (tm) ranging from 0.19% to 0.29% and corrected peak area (Ac) from 2.54% to 3.68%. The linearity of detector response was tested in the range 5–40 μg ml−1 obtaining the 0.9962 ≤ r2 ≤ 0.9982. LOD and LOQ, accuracy (recovery) and ruggedness were evaluated for each analyte demonstrating the good reliability of the method. Analysis of the pharmaceutical real sample was performed.

Improved rapid assay of plasma uric acid by short-end injection capillary zone electrophoresis

A rapid and simple short-end injection capillary zone electrophoresis method was developed for the quantification of plasma uric acid. The separation was performed in an uncoated fused-silica capillary (50 microm ID, 60 cm total length, 10.2 cm effective length) by using as a background electrolyte a 75 mmol/L glycylglycine solution titrated with NaOH 5 mol/L to pH 9.0, a voltage of 28 kV, a cartridge temperature of 15 degrees C, and direct UV detection at 292 nm. Under optimized conditions, uric acid was determinate in little more than 1 min (1.076 minutes). In order to verify the accuracy of the analysis, urate levels were measured in 543 apparently healthy volunteers by the new assay and our previous method, and the obtained data were compared by Passing-Bablock regression, Bland-Altman test, and a new regression-based approach, which showed a good agreement between two methods.

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.

Separation and Determination of β 2-Agonists in Swine Feed Using Field-Amplified On-Line Sample Stacking Method by Capillary Zone Electrophoresis

A rapid, simple, and reliable capillary zone electrophoresis method was developed for the separation and determination of β2-agonists under the optimum buffer solution consisting of 50 mM H3BO3-Na2B4O7 and 30 mM NaCl (pH 7.40). The field amplified sample stacking (FASS) technique was applied to the on-line concentration of β2-agonists cimaterol, clenbuterol, and salbutamol. The data presented in this work indicate that the sensitivity could be improved significantly by using a short water plug in FASS. Under the optimum conditions, cimaterol, clenbuterol, and salbutamol were separated completely and determined with the correlation coefficient of 0.9996 ∼ 0.9999. The relative standard deviations (RSD) were less than 2.85% (run to run) and 3.10% (day to day) for peak area. The detection ranges (S/N = 3) were located from 0.01 to 1 µg/mL for each β2-agonists. With this stacking measure, cimaterol, clenbuterol, and salbutamol in spiked swine feed were successfully determined with the recovery more than 95%.

Rapid Capillary Zone Electrophoresis Along Short Separation Pathways and Its Use in Some Hyphenated Systems: A Critical Review

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTRapid Capillary Zone Electrophoresis Along Short Separation Pathways and Its Use in Some Hyphenated Systems: A Critical ReviewFrantišek Opekar, Pavel Coufal, and Karel Štulík*View Author Information Charles University in Prague, Faculty of Science, Department of Analytical Chemistry, Albertov 2030, CZ-128 43 Prague 2, Czech RepublicCite this: Chem. Rev. 2009, 109, 9, 4487–4499Publication Date (Web):June 19, 2009Publication History Received16 January 2009Published online19 June 2009Published inissue 9 September 2009https://doi.org/10.1021/cr900018rCopyright © 2009 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views1497Altmetric-Citations49LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (457 KB) Get e-AlertsSUBJECTS:Capillary electrophoresis,Chromatography,Genetics,Interfaces,Peptides and proteins Get e-Alerts

Capillary zone electrophoresis method for the determination of famotidine and related impurities in pharmaceuticals

A simple and rapid capillary zone electrophoresis (CZE) method with UV detection has been developed for the determination of famotidine and its potential impurities in pharmaceutical formulations. The electrophoretic separation of these compounds was performed using a fused silica capillary and 37.5 mmol L −1 phosphate buffer pH 3.5 as the electrolyte. Under the optimised conditions, six impurities could be resolved from the famotidine peak in less than 7 min. The calibration curves obtained for the seven compounds were linear over the concentration range investigated (from 1.5 to 78.5 μg mL −1). The intra- and inter-day relative standard deviations for the migration times and corrected peak areas were less than 2% and 5%, respectively. The detection limits were found to be 0.09 μg mL −1 for famotidine, and from 0.1 to 0.62 μg mL −1 depending on the impurities. The method has been successfully applied to the determination of famotidine in commercial dosage 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.

Determination of major metal cations in milk by capillary zone electrophoresis

A reliable and rapid capillary zone electrophoresis method for the determination of the major of cations in milk samples was developed. Sample preparation consisted of dilution, acidification to pH 4.0 with 1 mol L −1 acetic acid and filtration. The complete separation of K +, Ca 2+, Na + and Mg 2+ could be achieved in 4 min with a simple electrolyte composed of 10 mmol L −1 imidazole and 1 mol L −1 acetic acid (pH 3.6). The running voltage was 25 kV at 25 °C. Indirect UV detection was achieved at 185 nm. Detection limits ranged from 0.06 to 0.57 mg L −1 and quantification limits ranged from 0.16 to 0.62 mg L −1. Precision data showed relative standard deviations (RSD%) lower than 4.1% for relative migration time and 2.4% for milk concentrations, respectively. Recoveries of cations in samples analysed ranged from 97.7% to 101.1%. Thirty samples of milk were analysed, obtaining mean values of 1.46, 1.19, 0.505 and 0.126 g L −1 for K +, Ca 2+, Na + and Mg 2+, respectively.

Simple determination of main organic acids in grape juice and wine by using capillary zone electrophoresis with direct UV detection

An accurate, simple and rapid capillary zone electrophoresis (CZE) method with direct UV detection has been set up for the determination of main organic acids in grape juice and wine. The determination of tartaric, malic, and citric acids in grape juices and tartaric, malic, succinic, acetic, lactic and citric acids in wines can be achieved in less than 3 min with only a simple dilution and filtration treatment of the sample. Validation parameters of the method as detection and quantification limits, linearity, precision (intraday and interday analysis) and recovery were also studied in grape juice, white wine, rose wine and red wine, separately. The proposed method decreases the analysis times of the previous reported CZE methods and allows the rapid control of the grape maturity, the winemaking processes and the detection of wine alterations and/or illnesses.

Rapid Determination of Nonaromatic Organic Acids in Honey by Capillary Zone Electrophoresis with Direct Ultraviolet Detection

A rapid capillary zone electrophoresis (CZE) method with direct ultraviolet (UV) detection has been set up and developed to determine the most important nonaromatic organic acids in honey with a really simple treatment of the sample. The determination of oxalic, formic, malic, succinic, pyruvic, acetic, lactic, citric, and gluconic acids has been carried out in 4 min. The electrolyte composition was phosphate as the carrier buffer (7.5 mM NaH(2)PO(4) and 2.5 mM Na(2)HPO(4)), 2.5 mM tetradecyltrimethylammonium hydroxide (TTAOH) as electroosmotic flow modifier, and 0.24 mM CaCl(2) as selectivity modifier, with the pH adjusted at 6.40 constant value. The running voltage was -25 kV at a thermostated temperature of 25 degrees C. The injections were performed in hydrodynamic mode (30 s), and the detection mode was UV direct at 185 nm. Validation parameters of the method as detection and quantification limits, linearity, precision (repeatability and reproducibility), and recovery were also studied. The advantages related to the technique such as simplicity, short analysis times, and low consumption of chemicals as well as the good validation parameters obtained for this method permit it to be considered as adequate for routine analysis in honey.

Rapid capillary zone electrophoresis method for the determination of metal cations in beverages

A rapid and reliable capillary zone electrophoresis method for the determination of inorganic cations was developed. The complete separation of K +, Ba 2+, Ca 2+, Na +, Mg 2+, Mn 2+, Ni 2+, Cd 2+, Li + and Cu 2+ can be achieved in 4 min with a simple electrolyte composed by 10 mM imidazole as the carrier buffer and background absorbance provider and acetic acid as the complexing agent (pH 3.60). Injection was performed hydrostatically by elevating the sample at 10 cm for 30 s. The running voltage was +25 kV at room temperature. Indirect UV-absorption detection was achieved at 185 nm. The detection limit was in the range between 0.06 mg/l (Mg 2+) and 0.57 mg/l (K +) and the quantification limits ranged from 0.10 mg/l (Ni 2+) to 0.80 mg/l (Cu 2+). The calibration graphs were linear in the concentration range from the quantification limit till at least 1 g/l in K +, 10 mg/l in Ba 2+, Ca 2+, Mg 2+, Mn 2+, Ni 2+ and Cd 2+, 40 mg/l in Na + and 12 mg/l in Li + and Cu 2+. The repeatability, intraday and interday analysis were ≤1.55% and ≤3.64% for migration time and ≤3.38% and ≤3.63% for peak area. The method developed has been applied to several beverage samples with only a simple dilution and filtration treatment of the sample. The proposed method is simple, fast, cheap and it is achieved with common products in either laboratory. For these reasons, it is a very useful method for routine analysis.

Rapid determination of aristolochic acid I and II in Aristolochia plants from different regions by β-cyclodextrin-modified capillary zone electrophoresis

Chinese herbs nephropathy (CHN) is a kind of severe kidney disease caused by excessively taking aristolochic acid (AA). Hence, it is essential for health security and quality control of related herbal medicines to develop an efficient method for separation and determination of these two important components in Traditional Chinese Medicines. In this study, a rapid capillary zone electrophoresis (CZE) method using 120 mM sodium borate buffer containing 10 mM β-cyclodextrin (β-CD) as modifier was firstly developed for the analysis of AA-I and AA-II within 4 min in some medicinal plant samples. The separation conditions including pH of running buffer, CD content in the buffer system, applied voltage and capillary temperature were systematically optimized, and two kinds of aristolochic acids in 37 herbal samples of Aristolochia plants were successfully determined with high separation efficiency, satisfactory sensitivity, repeatability and recovery. The result indicated high variability in the contents of aristolochic acids due to different species and regions. The comparison of CZE method with high performance liquid chromatography (HPLC) was also discussed.

Rapid determination of aristolochic acid I and II in Aristolochia plants from different regions by β-cyclodextrin-modified capillary zone electrophoresis

Chinese herbs nephropathy (CHN) is a kind of severe kidney disease caused by excessively taking aristolochic acid (AA). Hence, it is essential for health security and quality control of related herbal medicines to develop an efficient method for separation and determination of these two important components in Traditional Chinese Medicines. In this study, a rapid capillary zone electrophoresis (CZE) method using 120 mM sodium borate buffer containing 10 mM β-cyclodextrin (β-CD) as modifier was firstly developed for the analysis of AA-I and AA-II within 4 min in some medicinal plant samples. The separation conditions including pH of running buffer, CD content in the buffer system, applied voltage and capillary temperature were systematically optimized, and two kinds of aristolochic acids in 37 herbal samples of Aristolochia plants were successfully determined with high separation efficiency, satisfactory sensitivity, repeatability and recovery. The result indicated high variability in the contents of aristolochic acids due to different species and regions. The comparison of CZE method with high performance liquid chromatography (HPLC) was also discussed.

Determination of aristolochic acid by capillary zone electrophoresis

AbstractA simple and rapid capillary zone electrophoresis (CZE) method for the determination of aristolochic acid (AA) in dietary supplements and selected herbs is described. A clear separation of AA from other sample constituents was achieved within 5 minutes without any sample clean up. A mixture of 20 mM-morpholinethanesulphonic acid+10 mM-BisTrisPropane+0.2% hydroxyethylcelullose in 10% methanol serves as a background electrolyte. The linearity, accuracy, intra-assay and detection limit of the developed method are 200–6000 ng/mL, 95–103%, 3.5%, and 50 ng/ml, respectively. Ease of use, sufficient sensitivity and low running cost are the most important attributes of the CZE method. The proposed CZE method was compared with HPLC.

Determination of Rutin, Quercetin, and Chlorogenic Acid in Mulberry Leaves by Capillary Zone Electrophoresis

A simple, rapid, and accurate capillary zone electrophoresis (CZE) technique has been developed for the separation and determination of rutin, quercetin, and chlorogenic acid in mulberry leaves collected in different periods. The effects of various parameters, such as buffer concentration, pH value, and proportion of methanol on electrophoresis behaviors of the analytes, rutin, quercetin, and chlorogenic acid, were investigated. After a series of optimization, the separation of the three compounds in mulberry leaves was achieved successfully within 12 min in the buffer solution of 40 mmol · L−1 borax (pH 9.3). The linearity, limit of quantification, reproducibility, and recovery for all were satisfactory. The optimized CZE method proposed here has been satisfactorily employed to analyze real samples of mulberry leaves.

Validated Method for Simultaneous Determination of Cefepime and L‐Arginine in Cefepime for Injection by Capillary Zone Electrophoresis

A rapid and accurate capillary zone electrophoresis (CZE) method is described for simultaneous determination of cefepime and L‐arginine in cefepime for injection. Best results were achieved with the background electrolyte (BGE) prepared by titrating 40 mM sodium dihydrogen phosphate with phosphoric acid to pH 2.3 and an applied voltage of 30 kV in a bare fused‐silica capillary. The capillary temperature was 30°C and detection was made at 195 nm. L‐Histidine was used as internal standard (IS) to ensure acceptable precision. Separation was completed in less than 12 min. The optimized method was validated for selectivity, linearity, accuracy, precision, ruggedness, repeatability, and detection limits. The linear range for cefepime and L‐arginine was 57–571 and 39–394 µg mL−1, respectively. Limit of quantitation (LOQ) was 6 µg mL−1 for cefepime and 3 µg mL−1 for L‐arginine. Relative standard deviation (RSD) for peak area ratio (PAR, the area of analyte peak, divided by the area of the IS peak) was less than 1.0%.

Determination of valproic acid (2-propylpentanoic acid) in human plasma by capillary electrophoresis with indirect UV detection.

A rapid capillary zone electrophoresis method with indirect UV detection was developed and validated for the determination of valproic acid (VPA) in human plasma. The analyses were carried out under optimized conditions, using a buffer system composed of 15 mM benzoate and 0.5 mM cetyltrimethylammonium bromide at pH 6.0, and 25% v/v methanol; 2-hydroxybutyric acid was selected as the internal standard (IS). The capillary electrophoresis (CE) separation was carried out at a negative potential of 30 kV and the indirect UV detection was operated at 210 +/- 20 nm for all assays. The influence of buffer pH, ionic strength, concentration of electroosmotic flow (EOF) modifier and organic modifier on indirect signal response and migration behavior of the organic acid was investigated. Isolation of VPA from plasma was accomplished by a carefully implemented procedure using methanol as the precipitant agent. Using a high ratio of methanol to plasma for deproteinization (4:1), good absolute recovery of the analyte and satisfactory selectivity was obtained. The calibration line for VPA was linear over the 1-100 microg/mL concentration range. Sensitivity was high; in fact, the limit of detection (LOD) of VPA was 150 ng/mL and 450 ng/mL the limit of quantitation (LOQ). The results obtained analyzing real plasma samples from schizophrenic patients under polytherapy with VPA as well as antipsychotic drugs were satisfactory in terms of precision, accuracy and sensitivity.

Field-amplified sample stacking in capillary electrophoresis for on-column concentration of alkaloids in Sophora flavescens Ait.

A simple and rapid capillary zone electrophoresis method was developed for the separation of the main alkaloids from Sophora flavescens Ait. with the optimum buffer solution containing 110 mM NaH(2)PO(4) and 15% 2-propanol (pH 3.0). The field-amplified sample stacking (FASS) technique was applied to the on-line concentration of the alkaloids. The data presented in this work demonstrate that the use of a short water plug at the column inlet is essential for improving the reproducibility of FASS with electro-injection, and that the water plug injection time affected the sensitivity significantly. The sample concentration was further increased by about 2-3-fold by the introduction of a relatively longer water plug. With this stacking measure, the concentration sensitivity was about 3-4 orders of magnitude higher than in hydrodynamic injection.

Determination of grepafloxacin and clinafloxacin by capillary zone electrophoresis

A simple and rapid capillary zone electrophoresis determination method with UV detection of grepafloxacin and clinafloxacin has been developed. The separation was performed in 35 m M borate–35 m M phosphate buffer solution (pH 8.6), containing 6% (v/v) of acetonitrile. Analyses were realised using fused-silica capillaries (57 cm length×75 μm I.D.) and the operating conditions were: 15 kV applied voltage, 30 °C and detection at 279 nm. Piromidic acid was used as an internal standard. The linear concentration range of application was 1.0–120.0 μg ml −1 for both compounds, with a detection limit of 0.2 μg ml −1 for grepafloxacin and 0.3 μg ml −1 for clinafloxacin. The analysis yielded good reproducibility (RSD between 3.37 and 1.74%). It was applied to the determination of grepafloxacin and clinafloxacin in human and rat urine samples. The method was validated using HPLC as a reference method. Recovery levels were between 94.5 and 103%.