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1.
Ceska Gynekol ; 89(3): 196-202, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38969513

RESUMO

INTRODUCTION: Simulation medicine is no longer just a modern trend and has become a standard part of education and training of the medical staff and students in many countries around the world. Its validity and benefits have been acknowledged and its necessity is reflected in the recommendations of the European Board and College of Obstetrics and Gynaecology. OBJECTIVES: The aim of our work was to map the current state of simulation training at large obstetrics and gynaecology departments in the Czech Republic including the equipment available, teaching environment conditions and human resources and to find out to what extent individual teaching methods are being used in undergraduate and postgraduate education. METHODS: We have collected the information using a questionnaire which focused on the equipment available to the departments, teaching environment conditions, human resources, and types of simulation methods being used in undergraduate and postgraduate training as well as the spectrum of courses being offered. RESULTS AND CONCLUSION: Our finding is that large obstetrics and gynaecology departments in the Czech Republic are well equipped, have good teaching environments available to them, and are able to use most of the current simulation teaching methods. On the other hand, except for an operative vaginal birth course, only a small number of other simulation courses are currently being offered. Data from the survey are further used to discuss the possibilities of developing simulation training in this field in the Czech Republic.


Assuntos
Ginecologia , Obstetrícia , Treinamento por Simulação , República Tcheca , Ginecologia/educação , Obstetrícia/educação , Humanos , Treinamento por Simulação/métodos , Feminino , Inquéritos e Questionários
2.
Electrophoresis ; 36(24): 3069-79, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26377388

RESUMO

A new multidimensional analytical approach for the ultra-trace determination of target chiral compounds in unpretreated complex real samples was developed in this work. The proposed analytical system provided high orthogonality due to on-line combination of three different methods (separation mechanisms), i.e. (1) isotachophoresis (ITP), (2) chiral capillary zone electrophoresis (chiral CZE), and (3) triple quadrupole mass spectrometry (QqQ MS). The ITP step, performed in a large bore capillary (800 µm), was utilized for the effective sample pretreatment (preconcentration and matrix clean-up) in a large injection volume (1-10 µL) enabling to obtain as low as ca. 80 pg/mL limits of detection for the target enantiomers in urine matrices. In the chiral CZE step, the different chiral selectors (neutral, ionizable, and permanently charged cyclodextrins) and buffer systems were tested in terms of enantioselectivity and influence on the MS detection response. The performance parameters of the optimized ITP - chiral CZE-QqQ MS method were evaluated according to the FDA guidance for bioanalytical method validation. Successful validation and application (enantioselective monitoring of renally eliminated pheniramine and its metabolite in human urine) highlighted great potential of this chiral approach in advanced enantioselective biomedical applications.


Assuntos
Eletroforese Capilar/métodos , Preparações Farmacêuticas/química , Preparações Farmacêuticas/urina , Espectrometria de Massas em Tandem/métodos , Eletroforese Capilar/instrumentação , Desenho de Equipamento , Feminino , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Modelos Químicos , Preparações Farmacêuticas/isolamento & purificação , Reprodutibilidade dos Testes , Estereoisomerismo , Espectrometria de Massas em Tandem/instrumentação
3.
Ceska Slov Farm ; 64(5): 220-2, 2015 11.
Artigo em Inglês | MEDLINE | ID: mdl-28649823

RESUMO

The work was based on the identification and determination of selected elements in teas, plants and medicinal products for the treatment of anemia. To evaluate the quality of medicinal plants Urtica dioica L., Papaver somniferum, L., leguminous plant Lens culinaris, M. and also in medicaments Aktiferrin® gtt., Ferronat® retard pot.tbl and Sorbifer® Durulues® por. Tbl. Flm. was used nuclear analytical method Radionuclide X-ray Fluorescence Spectrometry. This method is suitable for the analysis of samples in the solid state and a liquid state. Solid samples were homogenized and compressed into tablets of defined shape and weight. Liquid samples were filtered through a chelating membrane 3M EmporeTM, which are used to selectively capture the polyvalent metal cations and are preconcentrating the elements from sample. Samples were analysed using radiation radionuclide 238 Pu and evaluated by means of a semiconductor detector and a multichannel analyser.


Assuntos
Anemia/tratamento farmacológico , Plantas Medicinais/química , Espectrometria por Raios X/métodos , Chá/química , Plutônio , Semicondutores
4.
J Sep Sci ; 36(11): 1805-16, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23494966

RESUMO

The present work illustrates potentialities of CE hyphenated with MS/MS for the simultaneous determination and identification of a mixture of simultaneously acting drugs in pharmaceutical and biological matrices. Here, the hyphenation was provided by ESI interface, while the MS/MS technique was based on the triple quadrupole configuration. Three drugs, namely pheniramine, phenylephrine, and paracetamol were determined and identified with high reliability due to their characterization in three different dimensions, i.e. electrophoresis and MS/MS, that prevented practically any interference. Appropriately selected transitions of the analytes (parent ion-quantifier product ion-qualifier product ion) provided their selective determination at maximum S/N. The proposed CE-MS/MS method was validated (LOD/LOQ, linearity, precision, recovery, accuracy) and applied for (i) the multidrug composition pharmaceuticals, namely Theraflu®, and (ii) human urine taken after per-oral administration of the same pharmaceutical preparation. The method was applied also for the investigation of potential weak associates of the drugs and monitoring of predicted (bio)degradation products of the drugs. Successful validation and application of the proposed method suggest its routine use in highly effective and reliable advanced drug control and biomedical research.


Assuntos
Acetaminofen/urina , Eletroforese Capilar/métodos , Espectrometria de Massas/métodos , Feniramina/urina , Fenilefrina/urina , Eletroforese Capilar/instrumentação , Humanos
5.
Electrophoresis ; 34(8): 1223-31, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23401242

RESUMO

An analytical method, based on a column coupling capillary ITP and CZE in a hydrodynamically closed separation mode hyphenated with the detection in the modular arrangement, was developed in this work. Analytical possibilities of this approach are demonstrated on the direct and ultrasensitive quantitative determination of quinine (QUI) in diluted real multicomponent ionic matrices (beverages, urine). The detection cell interface, with the rectangular arrangement of the optical channels inside, connected the separation capillary with the LIF detector via optical fibers in the on-column detection arrangement. ITP enabled the direct large volume (30 µL) injections of the diluted real matrices with an on-line sample pretreatment (preseparation, preconcentration) so that no external sample preparation (except for the dilution) was necessary for the separation of the analyte in the multicomponent ionic matrices. Due to the ITP sample preconcentration and intrinsic sensitivity of the LIF detection, very low concentration LOD (as low as 77 pg/mL), were reached at the same time. This was ca. two orders lower than the corresponding LOD achieved by the same 2D separation system with UV absorbance detection. Compared to the single column CE-LIF methods applied for this model analyte and matrix, this method was found to be superior in terms of concentration LOD, with acceptable selectivity and benefits of the on-line sample preparation. A food control and bioanalytical application clearly illustrates great practical possibilities and routine use of the proposed modular ITP-CZE-LIF technique.


Assuntos
Eletroforese Capilar/instrumentação , Eletroforese Capilar/métodos , Isotacoforese/instrumentação , Isotacoforese/métodos , Bebidas/análise , Feminino , Humanos , Limite de Detecção , Modelos Químicos , Quinina/análise , Quinina/isolamento & purificação , Quinina/urina , Reprodutibilidade dos Testes , Espectrometria de Fluorescência/métodos
6.
Talanta ; 103: 294-300, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23200390

RESUMO

Separation possibilities of three-dimensional (3D) capillary electrophoresis (CE) were studied in this work. They were demonstrated using phthalic acid as a model analyte and human urine as a complex ionic model matrix. Complexity of the selected problem ordering from several facts, such as (i) analyte present on a trace concentration levels, (ii) analyte present in multicomponent matrix and (iii) analyte migrating in the region of electropherogram in which is naturally present the majority of ionizable organic compounds (i.e. potential interfering compounds). 3D tandem was created by (i) isotachophoresis (ITP) preseparation stage (first), (ii) ITP analytical stage (second), and (iii) capillary zone electrophoresis (CZE) analytical stage (third). Comparison of 2D and 3D CE employing two and three different CE stages, respectively, revealed considerably enhanced separation capability of the 3D CE system. Although no single ITP was sufficient for the effective sample pretreatment, the mutual combination of these two ITP steps do it. The proposed ITP tandem was based on the different migration pattern of two spacers-analyte-matrix constituents under different acid-base conditions (pH 3.1 vs. pH 4.5 in ITP1 and ITP2, respectively), that can be, generally, very effective tool for acidic compounds present in multicomponent ionic matrices. Besides the enhanced separation selectivity/sample clean-up, the 3D CE method kept benefits of the hydrodynamically closed separation system with enhanced sample loadability, such as excellent (i) reproducibility of the measurements and (ii) concentration detection limits. Hence, this study clearly demonstrated great potentialities of 3D CE in the solving even the most advanced separation problems as can be found in bioanalytical field.


Assuntos
Eletroforese Capilar/métodos , Isotacoforese , Ácidos Ftálicos/isolamento & purificação , Urina/química , Eletroforese Capilar/instrumentação , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
7.
J Chromatogr Sci ; 50(10): 849-54, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22677486

RESUMO

The possibilities of a column coupling two-dimensional capillary electrophoresis (2D CE) combined with fiber-based diode array detection (DAD) for the direct, highly reliable and ultrasensitive quantitative determination of quinine in real multicomponent ionic matrices (human urine) are demonstrated in this work. The capillary isotachophoresis (CITP) stage provided an on-line sample pretreatment (elimination of interfering matrix constituents, preseparation and preconcentration of the analyte) before the capillary zone electrophoresis (CZE) separation. Due to the large volume (30 µL) sample injection and CITP sample preconcentration, a simple absorbance photometric detection was sufficient for obtaining very low concentration limits of detection (∼8.6 ng/mL). The combination of the different separation mechanisms (CITP and CZE) resulted in enhanced separation selectivity. This enabled us to obtain a pure analyte zone in the directly injected real samples suitable for qualitative and quantitative evaluation. The spectral DAD allowed (i) characterization of the purity (i.e., spectral homogeneity) of the analyte zone; and (ii) preliminary indication of structurally related compounds (i.e., potential biodegradation products of quinine), via characteristic spectra recorded in intervals of 200-800 nm. The CITP-CZE-DAD method was characterized by favorable performance parameters that are suitable for its routine biomedical use. One of the primary benefits of the CITP-CZE-DAD method is the possibility of performing direct injections of real biological samples while avoiding external sample preparation procedures and, therefore, enhancing the reliability and applicability of analyses and the potential for method automatization and miniaturization.


Assuntos
Eletroforese Capilar/métodos , Quinina/urina , Feminino , Humanos , Isotacoforese/métodos , Limite de Detecção , Reprodutibilidade dos Testes , Espectrofotometria/métodos
8.
Electrophoresis ; 29(22): 4561-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18975302

RESUMO

The present work illustrated possibilities of column-coupling electrophoresis combined with DAD for the direct quantitative determination of trace drug (celiprolol, CEL) in clinical human urine samples. ITP, on-line coupled with CZE, served as an ideal injection technique (high sample load capacity, narrow and sharp drug zone). Moreover, the ITP provided an effective on-line sample pretreatment (preseparation, purification and preconcentration of the drug) producing analyte zone suitable for its direct detection and quantitation in CZE stage. Spectral DAD in comparison with single wavelength ultraviolet detection enhanced value of analytical information (i) verifying purity (i.e., spectral homogeneity) of drug zone (according to differences in spectrum profiles when compared tested and reference drug spectra) and (ii) indicating zones/peaks with spectra similar to the drug spectrum (potential structurally related metabolites). The characterization of trace analyte signals superposed on the baseline noise was more definite thanks to the application of background correction and smoothing procedure to the raw DAD spectra (producing relevant spectral response). The proposed ITP-CZE-DAD method was characterized by favorable performance parameters for CEL in urine matrices {e.g., the lower limit of quantification was 9.7 ng/mL, RSD and relative error of the determinations were lower than 3% (precision) and 1% (accuracy), respectively, analyte peak exhibited spectral homogeneity (reflecting separation selectivity), separation efficiency was 84,500 theoretical plates} and successfully applied in a trial pharmacokinetic study of CEL.


Assuntos
Antagonistas Adrenérgicos beta/urina , Celiprolol/urina , Eletroforese Capilar/métodos , Eletroforese/métodos , Soluções Tampão , Feminino , Humanos , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Artigo em Inglês | MEDLINE | ID: mdl-18599368

RESUMO

The present work illustrates possibilities of column-coupling capillary electrophoresis (CE-CE) combined with chiral selector (2-hydroxypropyl-beta-cyclodextrin, HP-beta-CD) and fiber-based diode array detection (DAD) for the direct quantitative enantioselective determination of trace drug (amlodipine, AML) in biological multicomponent ionic matrices (human urine). Capillary isotachophoresis (ITP) served as an ideal injection technique in CE-CE. Moreover, the ITP provided an effective on-line sample pretreatment prior to the capillary zone electrophoresis (CZE) separation. Enhanced separation selectivity due to the combination of different separation mechanisms (ITP vs. CZE-HP-beta-CD) enabled to obtain pure zones of the analytes, suitable for their detection and quantitation. The DAD, unlike single wavelength UV detection, enabled to characterize the purity (i.e. spectral homogeneity) of the analytes zones. A processing of the raw DAD spectra (the background correction and smoothing procedure) was essential when a trace analyte signal was evaluated. Obtained results indicated pure (i.e. spectrally homogeneous) zones of interest confirming effective ITP-CZE separation process. The proposed ITP-CZE-DAD method was characterized by favorable performance parameters (sensitivity, linearity, precision, recovery, accuracy, robustness, selectivity) and successfully applied to an enantioselective pharmacokinetic study of AML.


Assuntos
Anlodipino/urina , Eletroforese Capilar/métodos , Eletroforese/métodos , Anlodipino/farmacocinética , Humanos , Masculino , Sistemas On-Line , Espectrofotometria Ultravioleta , Estereoisomerismo
10.
J Pharm Biomed Anal ; 46(5): 870-6, 2008 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-17618074

RESUMO

The present work illustrates potentialities of on-line combined isotachophoresis-capillary zone electrophoresis (ITP-CZE) separation techniques coupled with on-capillary diode array detector (DAD) for enantiomeric purity testing of drugs in pharmaceuticals. The general advantages of the proposed method are its (i) high selectivity, (ii) low concentration limit of detection (LOD) obtainable, (iii) enhanced sample loadability, and (iv) enhanced reliability. For separation of brompheniramine (BP) enantiomers, serving as model analytes, carboxyethyl-beta-cyclodextrin (CE-beta-CD) was appropriate chiral selector providing complete enantioresolution. Given by a high sample load capacity (30 microl sample injection volume) and preconcentration of the analytes in ITP stage, concentration LOD of levobrompheniramine (LBP), serving as model impurity, was 2.5 ng/ml (8 x 10(-9)mol/l). Such separation and detection conditions enabled to easily determine LBP in samples containing a 10(3) excess of dexbrompheniramine (DBP). DAD detection in comparison with single wavelength detection can enhance value of analytical information when analytes and interferents have different spectra (distinguishing impurities in analyte zone, confirmation of migration positions of migrants). In this context purity of BP zones was confirmed with higher reliability in pharmaceutical sample. Moreover, distinguishing the trace analyte signal superposed on the baseline noise was provided with sufficient reliability (for this purpose the background correction and smoothing procedure had to be applied to the raw DAD spectra). Successful validation and application of the proposed ITP-CZE-DAD method suggest its routine use for the enantiomeric purity testing of pharmaceuticals.


Assuntos
Bromofeniramina/isolamento & purificação , Eletroforese Capilar , Eletroforese , Tecnologia Farmacêutica/métodos , Bromofeniramina/química , Contaminação de Medicamentos/prevenção & controle , Eletroforese/normas , Eletroforese Capilar/normas , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Estereoisomerismo , Comprimidos , Tecnologia Farmacêutica/normas , beta-Ciclodextrinas/química
11.
J Chromatogr A ; 1179(1): 9-16, 2008 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-17905259

RESUMO

The present work illustrated possibilities of column coupling electrophoresis combined with ionizable chiral selector and diode array detection (DAD) for the enantioselective analysis of trace drugs (pheniramine and its analogs) in pharmaceutical and clinical samples. Isotachophoresis (ITP), on-line coupled with capillary zone electrophoresis (CZE), served as an ideal injection technique (high sample load capacity, narrow and sharp drugs zones) of on-line pretreated samples (preseparation, purification and preconcentration of drugs) for the CZE stage. Enhanced (enantio)separation selectivity of CZE with ionizable chiral selector (carboxyethyl-beta-cyclodextrin recognized between drugs enantiomers on one hand as well as between drugs and sample matrix constituents on the other hand) enabled to obtain pure zones of the drugs enantiomers, suitable for their detection and quantitation. DAD in comparison with single wavelength UV detection enhanced value of analytical information verifying purity of drugs enantiomers zones (indicating interferents with different spectra to those of drugs). Obtained results indicated pure zones of interest confirming effective ITP-CZE (enantio)separation process. Distinguishing the trace analytes signals superposed on the baseline noise was provided with sufficient reliability (for this purpose the background correction and smoothing procedure had to be applied to the raw DAD spectra). The proposed ITP-CZE-DAD methods were characterized by favorable performance parameters (sensitivity, linearity, precision, recovery, accuracy, robustness, selectivity) and successfully applied for (i) enantiomeric purity testing of dexbrompheniramine in commercial pharmaceutical tablets and (ii) enantioselective metabolic study of pheniramine in human urine.


Assuntos
Bromofeniramina/análise , Eletroforese Capilar/métodos , Eletroforese/métodos , Preparações Farmacêuticas/análise , Feniramina/análise , Bromofeniramina/isolamento & purificação , Humanos , Preparações Farmacêuticas/isolamento & purificação , Feniramina/isolamento & purificação , Feniramina/urina , Reprodutibilidade dos Testes , Estereoisomerismo
12.
Drug Dev Ind Pharm ; 33(11): 1199-204, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18058316

RESUMO

Cyclodextrin-mediated capillary isotachophoresis (ITP) in cationic regime of the separation was developed for the separation and quantitation of alkylamine antihistamine dimethindene (DIM) and pheniramine (PHM) enantiomers in various pharmaceutical preparations (capsules, oral drops, gel, granulated powder). Several electrolyte systems of different compositions and pH were examined. The optimized chiral ITP electrolyte system was consisted of 10 mmol/L potassium acetate adjusted to pH 4.8 with acetic acid, containing 4 mmol/L negatively charged CE-beta-CD (chiral selector) as the leading electrolyte with electroosmotic flow (EOF) suppressing additive, 0.2% (w/v) methylhydroxyethylcellulose (m-HEC), and 5 mmol/L beta-alanine as the terminating electrolyte. The proposed electrophoretic method was successfully validated. It was convenient for the sensitive, simple, rapid, and highly reproducible assay of these antihistamine enantiomers. The calibration graphs relating the ITP zone length to the concentration of DIM and PHM enantiomers were rectilinear (r = 0.999) in the range 40.0-200.0 mg/L of each enantiomer. The relative standard deviations (RSD) were 0.75% for DIM(1), 0.63% for DIM(2), 1.05% for PHM(1), and 0.83% for PHM(2) (n = 6) when determining 100 mg/L DIM and PHM, respectively, standard solutions. According to the validation procedure based on the standard addition technique the recoveries were 97.66-98.34%. Good quantitation was obtained in short analysis time (a single analysis took about 12 min). The minimal sample pretreatment and low running costs make the proposed ITP method a good alternative to commonly used analytical methods (CZE, HPLC). The obtained results suggest that the proposed method is suitable for routine assay of dimethindene and pheniramine enantiomers in various pharmaceuticals.


Assuntos
Ciclodextrinas/química , Dimetideno/química , Eletroforese Capilar/métodos , Antagonistas dos Receptores Histamínicos H1/química , Feniramina/química , Estereoisomerismo
13.
Electrophoresis ; 28(15): 2738-47, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17600843

RESUMO

Application potentialities of CZE on-line coupled with capillary ITP and DAD to the identification and determination of trace concentration levels (microg/L) of pheniramine (PHM) enantiomers and their metabolites present in complex ionic matrices of biological origin (urine) are shown. An enhanced (enantio)selectivity of the CZE separation system obtained by the addition of carboxyethyl-beta-CD (CE-beta-CD) to the carrier electrolyte provided CZE conditions for a reliable identification of similar/identical DAD spectra of structurally related compounds (PHM enantiomers and their metabolites) in clinical urine samples differing in qualitative and quantitative composition of sample matrix constituents. A high sample loadability (a 30 microL sample injection volume), partial sample clean-up (removing macroconstituents from the sample), and preconcentration of the analytes in ITP stage resulted in the decrease of concentration LOD for PHM enantiomers in urine to 5.2 and 6.8 microg/L (2.2 x 10(-8) and 2.8 x 10(-8) mol/L), without using any sample pretreatment technique. The background correction and smoothing procedure applied to the raw DAD spectra provided analytically relevant DAD spectra of PHM enantiomers and their metabolites also when they were present in urine sample (30 microL injection volumes of ten-times diluted urine sample) at a 9 x 10(-) (8) mol/L concentration. DAD spectra of PHM enantiomers present in urine samples matched their reference spectra with reasonable certainties. DAD spectra of PHM metabolites were compared with the reference spectra of PHM enantiomers and a good match was found which indicates the similarities in the structures of enantiomers and their metabolites detected in the urine samples. This fact allows performing the quantitative analyses of PHM metabolites in the urine samples by applying the calibration parameters of PHM enantiomers also for PHM metabolites and the results show the possibilities of using the ITP-CZE-DAD combination for the direct analysis of PHM enantiomers and/or their metabolites in urine without any sample pretreatment. ITP-CZE-DAD method with oppositely charged selector is suggested to use in clinical research as it provides favorable performance parameters including sensitivity, linearity, precision, recovery, and robustness with minimal demands on sample preparation.


Assuntos
Eletroforese Capilar/métodos , Feniramina/urina , Ciclodextrinas , Eletroforese Capilar/normas , Feniramina/metabolismo , Estereoisomerismo
14.
Arch Pharm (Weinheim) ; 339(2): 96-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16425316

RESUMO

Capillary isotachophoresis (ITP) in cationic regime of the separation with conductometric detection has been used for the separation and determination of basic amino acids (arginine, histidine, and lysine) in pharmaceutical preparations. Several electrolyte systems of different compositions and pH were examined. The optimized ITP electrolyte system consisted of 10 mmol/L potassium acetate adjusted to pH 4.0 with acetic acid as the leading electrolyte with the electroosmotic-flow (EOF) suppressing additive, 0.2% (w/v) methylhydroxyethylcellulose (m-HEC), and 10 mmol/L beta-alanine as the terminating electrolyte. The proposed electrophoretic method was successfully validated. It was convenient for the sensitive, simple, rapid and highly reproducible assay of these amino acids. Good quantitation was obtained in short analysis times (a single analysis took about 10 min). The minimal sample pretreatment and low running costs make the proposed ITP method a good alternative to commonly used analytical methods. The obtained results suggest that the proposed method is suitable for routine assay of basic amino acids in pharmaceuticals.


Assuntos
Aminoácidos Essenciais/análise , Eletroforese Capilar/métodos
15.
Talanta ; 70(4): 840-6, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18970848

RESUMO

The possibility to apply charged chiral selector as buffer additive in capillary zone electrophoresis (CZE) on-line coupled with capillary isotachophoresis (CITP) was studied. Enantioseparations and determinations of trace (ng/ml) antihistaminic drugs [pheniramine (PHM), dimethindene (DIM), dioxopromethazine (DIO)] present in samples of complex ionic matrices (urine) served as model examples. A negatively charged carboxyethyl-beta-cyclodextrin (CE-beta-CD) was used as a chiral selector in analytical CZE stage following upon a sample pretreatment by CITP (preconcentration of the analytes from 5 to 20-times diluted urine samples, partial sample clean up removing macroconstituents from the sample matrices). A high recognition capability of the oppositely charged CE-beta-CD was demonstrated by enantioselective retardation of the drugs in presence of micro-and semi-macroconstituents migrating in CZE stage and detectable by UV detector. In this way, enantiomers of the drugs could be easily separated and determined. Due to lack of interferences between the drugs and sample-matrix constituents in presence of charged CE-beta-CD, demands on both spacers in CITP step and multiple column-switching were minimized. CITP-CZE method with charged selector appeared to be a useful analytical approach for the trace enantiomers in complex ionic matrices as it combined enhanced separation selectivity and sample loadabitlity with high separation efficiency and provided favorable performance parameters including sensitivity, linearity, precision, accuracy/recovery and robustness with minimal demands on sample preparation. Analysis of urine sample taken from a patient treated by PHM, showing concentration profile of PHM enantiomers and their metabolites, illustrated potentialities of the method in clinical research.

16.
Drug Dev Ind Pharm ; 31(8): 795-801, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16221614

RESUMO

Capillary electrophoresis (CE) methods for the determination of fexofenadine (FEX) in commercial pharmaceuticals were developed. It was demonstrated that FEX could be effectively analyzed in free solution cationic CE at low pH. Another analytical approach studied was based on cyclodextrin (CD) modified CE where highly charged CD derivatives served as analyte carriers. In this way, the separation range was spread to physiological pH region and a CE analysis of FEX, present actually in its zwitterionic form, could be accomplished. Several parameters affecting the separations were studied, including the type and concentration of carrier ion, counterion, analyte carrier, and pH of the buffer. The methods based on the free solution CE and CD-modified CE were compared each other, validated, and applied for the determination of FEX in tablets.


Assuntos
Química Farmacêutica/métodos , Terfenadina/análogos & derivados , beta-Ciclodextrinas/química , Antialérgicos/análise , Portadores de Fármacos , Eletrólitos/química , Eletroforese Capilar , Antagonistas dos Receptores Histamínicos H1/análise , Comprimidos , Terfenadina/análise
17.
Arch Pharm (Weinheim) ; 338(10): 498-501, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16211658

RESUMO

A capillary electrophoresis (CE) method for the separation and determination of salbutamol (SAL) in commercial pharmaceuticals was developed. Several parameters affecting the separations were studied including type and concentration of the carrier ion, counter ion, and the pH of the buffer. A hydrodynamically closed CE separation mode employing a 300 mum I.D. capillary, dynamically coated by polymeric buffer additive, provided good performance parameters (precision, accuracy, sensitivity). The obtained results suggest that the proposed method is suitable for routine assay of SAL in pharmaceutical preparations and can be used as an alternative to the conventional open CE mode for this application.


Assuntos
Agonistas Adrenérgicos beta/análise , Albuterol/análise , Preparações Farmacêuticas/química , Eletrólitos , Eletroforese Capilar , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Comprimidos
18.
J Sep Sci ; 28(12): 1278-84, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16138679

RESUMO

The present paper demonstrates the potential of cyclodextrin (CD)-mediated CE for the chiral analysis of a drug of zwitterionic nature, viz. cetirizine (CET). Various separation mechanisms were applied and several parameters affecting the separation were studied, including the type and concentration of chiral selector, coselector, and carrier ion, and pH of buffer. The optimal separation conditions were based on a medium buffer pH (approximately 5.2) (migration velocity of CET molecule was near to zero) and a highly substituted CD derivative, sulfated-beta-CD, serving as an analyte carrier in the anionic regime of the separation with suppressed electroosmotic flow. In this way, a baseline enantioseparation, reasonable separation efficiency, and short analysis time could be easily achieved. Acceptable validation criteria for sensitivity, linearity, precision, accuracy, and robustness were obtained using a hydrodynamically closed CE separation system. The proposed method was successfully applied to the enantioselective assay of CET in pharmaceutical formulations using fexofenadine (FEX) as an internal standard.

19.
J Pharm Biomed Anal ; 38(3): 442-8, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15925245

RESUMO

Cyclodextrin (CD)-mediated capillary zone electrophoresis (CZE) in hydrodynamically closed separation system was developed for the separation and quantitation of pheniramine (PHM) enantiomers. Several parameters affecting the separation were studied, including the type and concentration of chiral selector, carrier cation and counterion, and the pH of the buffer. A high effectivity of oppositely migrating carboxyethyl-beta-cyclodextrin (CE-beta-CD) to separate the PHM enantiomers was demonstrated in detail. The optimized chiral analysis of the antihistamine drug was performed in a buffer consisted of 20 mmol/l epsilon-aminocaproic acid adjusted to pH 4.5 with acetic acid, containing negatively charged CE-beta-CD (2.5 mg/ml) as chiral selector and 0.2% (w/v) methylhydroxyethylcellulose (m-HEC) as an electro-osmotic flow (EOF) suppressor. Acceptable validation criteria for sensitivity, linearity, precision, accuracy/recovery were included. The proposed CZE method was successfully applied to the assay of PHM in pharmaceutical formulations using dioxopromethazine as an internal standard.


Assuntos
Ciclodextrinas/química , Eletroforese Capilar/métodos , Antagonistas dos Receptores Histamínicos H1/análise , Feniramina/análise , Antagonistas dos Receptores Histamínicos H1/química , Estrutura Molecular , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Feniramina/química , Reprodutibilidade dos Testes , Estereoisomerismo , Tecnologia Farmacêutica/métodos , Tecnologia Farmacêutica/tendências
20.
Talanta ; 65(4): 1031-7, 2005 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-18969906

RESUMO

A capillary electrophoresis method has been developed for the separation and determination of terbinafine (TER) in various pharmaceutically relevant matrices. Capillary zone electrophoresis (CZE) separation and UV absorbance photometric detection were carried out in a 160mm capillary tube with a 300mum i.d., hydrodynamically (membrane) closed. The influences of pH, carrier cation and counterion on migration parameters of TER were studied and the following conditions were selected: a 20mmoll(-1) glycine running buffer adjusted to pH 2.7 with acetic acid, 0.2% (w/v) methylhydroxyethylcellulose (m-HEC) as an electro-osmotic flow (EOF) suppressor, a 250muA driving current, and 20 degrees C. The optimized separation conditions were convenient for the determination of TER in commercial tablets and spray and in dialyzates. Here, the dialysis was used to investigate in vitro permeation of TER through the skin from the gel. The samples of dialyzates were examined with and without simple extraction procedure and the results were compared. A permeation profile of the drug present in the gel of given composition was obtained analyzing pretreated samples. The proposed electrophoretic method was successfully validated. It was suitable for the simple, sensitive, rapid and highly reproducible assay of TER. CZE analysis was completed within 5.5min. The detection limit of TER was 1.73mumoll(-1) at a 224nm detection wavelength. The intra- and inter-laboratory precisions over the concentration range 6.0-60.0mumoll(-1) were between 0.32-0.69% and 1.04-1.44% including R.S.D. of migration times and peak areas, respectively. The mean absolute recoveries of drugs from samples were found to be 98.34 (tablets) and 99.47% (spray). It is suggested that there are potentialities to determine TER present in unpretreated complex samples, as CZE in a hydrodynamically closed separation system may be easily on-line combinable with purification and preconcentration CE modes (e.g., isotachophoresis, ITP).

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