Publications (33)63.52 Total impact
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Article: Biological safety studies of gemifloxacin mesylate and related substances.
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ABSTRACT: Purpose: The aim of this study was to evaluate the cytotoxic, phototoxic, genotoxic and photogenotoxic potential of gemifloxacin mesylate (GFM), its main synthetic impurity (SI) and one isolated and structurally elucidated degradation product (DP). Methods: The neutral red uptake (NRU) and reduction of 2,5-diphenyl-3,-(4,5-dimethyl-2-thiazolyl)tetrazolium bromide (MTT) assays were performed as in vitro endpoints to evaluate cytotoxicity and phototoxicity in a 3T3 cell line, and predict toxicity and/or phototoxicity after systemic administration of the drug. The in vitro alkaline single-cell electrophoresis (comet) assay was used to evaluate the genotoxic and photogenotoxic potential of the substances using the same cell line. Results: The results showed that the SI and the DP are more cytotoxic and phototoxic than the drug GFM using the 3T3 cell line. In the comet assay, the drug GFM was found to be more genotoxic and photogenotoxic than its related substances. Conclusions: Our findings highlight the relevance of the biological safety studies to increase the knowledge regarding the toxic potential of the related substances, which can be associated with the drug side effects and toxicity.Photochemical and Photobiological Sciences 01/2013; · 2.58 Impact Factor -
Article: Simultaneous determination of aliskiren and hydrochlorothiazide from their pharmaceutical preparations using a validated stability-indicating MEKC method.
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ABSTRACT: A stability-indicating MEKC method was developed and validated for the simultaneous determination of aliskiren (ALI) and hydrochlorothiazide (HCTZ) in pharmaceutical formulations using ranitidine as an internal standard (IS). Optimal conditions for the separation of ALI, HCTZ and its major impurity chlorothiazide (CTZ), IS and degradation products were investigated. The method employed 47 mM Tris buffer and 47 mM anionic detergent SDS solution at pH 10.2 as the background electrolyte. MEKC method was performed on a fused-silica capillary (40 cm) at 28°C. Applied voltage was 26 kV (positive polarity) and photodiode array (PDA) detector was set at 217 nm. The method was validated in accordance with the ICH requirements. The method was linear over the concentration range of 5-100 and 60-1200 μg/mL for HCTZ and ALI, respectively (r(2) >0.9997). The stability-indicating capability of the method was established by enforced degradation studies combined with peak purity assessment using the PDA detection. Precision and accuracy evaluated by RSD were lower than 2%. The method proved to be robust by a fractional factorial design evaluation. The proposed MEKC method was successfully applied for the quantitative analysis of ALI and HCTZ both individually and in a combined dosage tablet formulation to support the quality control.Journal of Separation Science 06/2011; · 2.73 Impact Factor -
Article: Fesoterodine stress degradation behavior by liquid chromatography coupled to ultraviolet detection and electrospray ionization mass spectrometry.
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ABSTRACT: In the present study, a rapid validated stability-indicating LC method was established and comprehensive stress testing of fesoterodine was carried out according to ICH guidelines. Fesoterodine was subjected to stress conditions of acid and basic hydrolysis, oxidation, photolysis and thermal decomposition. The degradation products formed under stress conditions were investigated by LC-UV and LC-ESI-MS. Successful separation of the drug from its degradation products was achieved on a monolithic C(18) column (100 mm × 4.6mm i.d.) maintained at 45°C using acetonitrile-methanol-0.03 mol L(-1) ammonium acetate (pH 3.8) (30:15:55, v/v/v) as the mobile phase. The flow rate was 2.4 mL min(-1) and the detection wavelength was 208 nm. Validation parameters such as specificity, linearity, precision, accuracy, and robustness were evaluated. Chromatographic separation was obtained within 2.5 min and it was suitable for high-throughput analysis. Fragmentation patterns of degradation products formed under different stress conditions were studied and characterized through LC-ESI-MS fragmentation. Based on the results, a drug degradation pathway was proposed, and the validated LC method was successfully applied to the quantitative analysis of fesoterodine in tablet dosage forms, helping to improve quality control and to assure therapeutic efficacy.Talanta 05/2011; 84(4):1068-79. · 3.79 Impact Factor -
Article: Gemifloxacin mesylate (GFM) stability evaluation applying a validated bioassay method and in vitro cytotoxic study.
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ABSTRACT: The validation of a microbiological assay applying the cylinder-plate method to determine the quinolone gemifloxacin mesylate (GFM) content is described. Using a strain of Staphylococcus epidermidis ATCC 12228 as the test organism, the GFM content in tablets at concentrations ranging from 0.5 to 4.5 μg mL(-1) could be determined. A standard curve was obtained by plotting three values derived from the diameters of the growth inhibition zone. A prospective validation showed that the method developed is linear (r=0.9966), precise (repeatability and intermediate precision), accurate (100.63%), specific and robust. GFM solutions (from the drug product) exposed to direct UVA radiation (352 nm), alkaline hydrolysis, acid hydrolysis, thermal stress, hydrogen peroxide causing oxidation, and a synthetic impurity were used to evaluate the specificity of the bioassay. The bioassay and the previously validated high performance liquid chromatographic (HPLC) method were compared using Student's t test, which indicated that there was no statistically significant difference between these two validated methods. These studies demonstrate the validity of the proposed bioassay, which allows reliable quantification of GFM in tablets and can be used as a useful alternative methodology for GFM analysis in stability studies and routine quality control. The GFM reference standard (RS), photodegraded GFM RS, and synthetic impurity samples were also studied in order to determine the preliminary in vitro cytotoxicity to peripheral blood mononuclear cells. The results indicated that the GFM RS and photodegraded GFM RS were potentially more cytotoxic than the synthetic impurity under the conditions of analysis applied.Talanta 02/2011; 83(5):1774-9. · 3.79 Impact Factor -
Article: Stability indicating LC method to determination of sodium montelukast in pharmaceutical dosage form and its photodegradation kinetics.
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ABSTRACT: Reversed-phase high performance liquid chromatography (LC) method is developed for the assay of sodium montelukast in coated tables and its photodegradation kinetics. An isocratic LC separation is performed on a Zorbax XDB C18 column using a mobile phase of acetonitrile-methanol-water (pH 3.8) (75:10:15, v/v/v) at a flow rate of 0.8 mL/min and detection at 280 nm. The detector response for sodium montelukast is linear over the concentration range from 5-35 μg/mL (r = 0.9999). The specificity of the method is proved using stress conditions. The solutions are exposed to UV radiation (352 nm), alkaline and acid hydrolysis, oxidation, and temperature (80 °C). The intra- and inter-day precision show suitable results (RSD < 0.49%). The accuracy of analytical method is 100.04% (RSD = 0.44%). Detection and quantification limits are 0.10 and 0.32 μg/mL respectively. The robustness of the method is assured after small changes in chromatographic conditions. The kinetic of photodegradation using a LC method is established and it can be described by zero-order kinetics. This developed method show to be viable for the determination of sodium montelukast in pharmaceutical dosage form and satisfactory in the determination of the kinetics of degradation.Journal of chromatographic science 01/2011; 49(7):540-6. · 0.88 Impact Factor -
Article: LC determination of entacapone in tablets: in vitro dissolution studies.
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ABSTRACT: The aim of the study was to develop and validate a dissolution procedure for entacapone-coated tablets. Several conditions such as medium composition, pH, surfactant concentration, and rotation speed were evaluated. The best dissolution conditions were achieved using apparatus 2, 900 mL of medium containing acetate buffer pH 5.3 at a rotation speed of 50 rpm, and a reversed-phase liquid chromatographic method for the quantification of the drug from the dissolution test, as well as to evaluate the dissolution profiles for tablets. The procedure was validated by specificity, linearity, accuracy, repeatability, intermediate precision, and robustness. The chromatographic method employed an Agilent Eclipse XDB RP-18 (150 × 4.6 mm i.d., particle size 5 μm) with a mobile phase consisting of water pH 3.0 and acetonitrile (65:35, v/v) at a flow rate of 2.0 mL/min. The dissolution procedure developed and validated was adequate for its purpose and could be applied for quality control for entacapone-coated tablets because there is no official monograph.Journal of chromatographic science 01/2010; 48(9):755-9. · 0.88 Impact Factor -
Article: Determination of fesoterodine in pharmaceutical formulations by using liquid chromatography-tandem mass spectrometry.
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ABSTRACT: A simple, fast, sensitive, and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the analysis of fesoterodine (FESO) in pharmaceutical formulations was developed and validated using manidipine as internal standard (IS). The LC-MS/MS method was carried out on a Luna C8(2) column (50 mm × 3.0 mm i.d., µm) with a mobile-phase consisting of methanol/0.1% formic acid (90:10, v/v). The mass spectrometry method was performed employing a positive electrospray ionization technique, operating in multiple reaction monitoring mode (MRM), monitoring the transitions of 412.2→223.0 and 611.1→167.0 for FESO and IS, respectively. The total analysis time was 2 min and it was linear in the concentration range of 5-1000 ng mL(-1). Placebo solution and mobile-phase components were evaluated on the specificity test and did not interfere with the analyte or the IS. Intra-day and inter- day precision and accuracy evaluated by RSDs and relative errors, respectively, were lower than 5% for all analytes. The method proved to be robust by a fractional factorial design evaluation. The proposed method was successfully applied for the quantitative analysis of FESO in tablet formulations to support the quality control.European Journal of Mass Spectrometry 01/2010; 16(6):653-61. · 1.21 Impact Factor -
Article: Isolation and structure elucidation of photodegradation products of fexofenadine.
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ABSTRACT: The photostability of the antihistamine fexofenadine hydrochloride is described. The stress studies revealed the photostability of the drug as the most adverse stability factor. The main photodegradation products were isolated and its structures were elucidated by 1H, 13C, COSY, HSQC, HMBC NMR and mass spectrometry techniques. The drug was exposed to UVC light at 254 nm in methanolic solutions and the degradation was followed by HPLC and TLC. The photostability of fexofenadine tablets was studied and the same degradation products were observed. The two photodegradation products isolated were characterized as the isopropyl derivative, obtained by decarboxilation of fexofenadine, and a benzophenone compound, which was obtained by rearrangement of aromatic rings and oxidation reactions. The results show the importance of appropriate light protection during the drug development process, storage and handling.Journal of Pharmaceutical and Biomedical Analysis 02/2008; 46(2):250-7. · 2.97 Impact Factor -
Article: Structural elucidation of rabeprazole sodium photodegradation products.
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ABSTRACT: Rabeprazole sodium is a proton pump inhibitor, used in acid-related disorders, like peptic ulcers and gastroesophageal reflux. It is known to be an acid-labile drug, however, few data about its stability under other factors are available. The aim of this work was to study the photodegradation of rabeprazole, to determine its kinetics and to elucidate the structures of the main degradation products. UVC-254 nm and metal-halide lamps were used. The analysis of the samples was carried out by HPLC. When the drug was in methanol solution, one main degradation product was formed; the degradation rate followed zero-order kinetics. The (1)H and (13)C NMR spectroscopic determinations revealed the product was the benzimidazolone. Another isolated product was identified as benzimidazole. The latter was confirmed against an authentic sample. A third photodegradation product was identified as the [4-(3-methoxy-propoxy)-3-methyl-pyridin-2-yl]methanol, by (1)H and (13)C NMR of the reaction mixture in chloroform-d. When powdered commercial tablets were exposed to UVC irradiation, they showed the same degradation products along with other unidentified, which appeared as traces; the degradation rate was slower than in solution. The intact tablets were stable after 50 days of exposition to the same light source.Journal of Pharmaceutical and Biomedical Analysis 02/2008; 46(1):88-93. · 2.97 Impact Factor -
Article: Dissolution test for citalopram in tablets and comparison of in vitro dissolution profiles.
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ABSTRACT: A dissolution test for tablets containing 20 mg of citalopram was developed and validated using a reverse-phase liquid chromatographic method and this dissolution test was applied to compare dissolution profiles. The sink conditions, filters, stability of the drug and specificity on different dissolution media were tested to choose a discriminatory dissolution method which uses USP apparatus 1 with baskets rotating at 50 rpm, 900 ml of deaerated 0.1 M hydrochloric acid (HCl) as the dissolution medium. The quantitation method was also adapted and validated. The parameters of difference factor, similar factor, according to current FDA guidelines, and dissolution efficiency were employed to compare dissolution profiles. The dissolution test developed and validated was adequate for its purposes and could be applied for quality control of citalopram tablets, since there is no monograph to citalopram in tablets, this work can be used to help pharmocopoeias.European Journal of Pharmaceutics and Biopharmaceutics 09/2007; 67(2):524-30. · 4.27 Impact Factor -
Article: Development and validation of a dissolution test for rabeprazole sodium in coated tablets.
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ABSTRACT: The aim of this work is to develop and validate a dissolution test for rabeprazole sodium coated tablets using a reverse-phase liquid chromatographic method. After test sink conditions, dissolution medium and stability of the drug, the best conditions were: paddle at 75 rotations per minute (rpm) stirring speed, HCl 0.1 M and borate buffer pH 9.0 as dissolution medium for acidic and basic steps, respectively, volume of 900 ml for both. The quantitation method was also adapted and validated. Less than 10% of the label amount was released in the acid step, while more than 95% was achieved over 30 min in the basic one. The dissolution profile for tablets was considered satisfactory. The dissolution test developed was adequate for its purpose and could be applied for quality control of rabeprazole tablets, since there is no official monograph.Journal of Pharmaceutical and Biomedical Analysis 07/2006; 41(3):833-7. · 2.97 Impact Factor -
Article: Stability and degradation kinetics of meropenem in powder for injection and reconstituted sample.
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ABSTRACT: The stability of broad-spectrum antibiotic meropenem was studied in order to investigate the kinetics of degradation of this drug in powder for injection and reconstituted sample. Carbapenem was submitted to conditions of accelerated thermal decomposition. Degradation of meropenem was adequately modeled by specific equations for order rate kinetics. The analyses of the degraded samples were performed by high-performance liquid chromatographic (HPLC) method and microbiological assay. At higher temperatures, the decomposition reactions of meropenem in powder for injection could be described by first-order kinetics. The higher rate of degradation was observed in meropenem reconstituted in 0.9% sodium chloride, and the thermal decomposition obeyed also first-order kinetics. The results obtained confirm the reliability of chromatographic method for determining the kinetics run of meropenem in the presence of its degradation products. The present study reveals the thermal lability of the drug, especially as reconstituted sample. Thus, appropriate thermal protection is recommended during the storage and handling.Journal of Pharmaceutical and Biomedical Analysis 07/2006; 41(4):1363-6. · 2.97 Impact Factor -
Article: Comparison of Microbiological and UV-Spectrophotometric Assays for Determination of Voriconazole in Tablets
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ABSTRACT: Two methods have been developed for the determination of voriconazole, a new antifungal drug, in tablets. A UV method, with detection at 255 nm, was compared with a diffusion agar bioassay, which used Sacharomyces cerevisiae ATCC 2601 as the assay organism. The developed methods were linear in the range of 3.012.0 and 12.024.0 g/mL, for the microbiological and UV methods, respectively, both exhibiting a coefficient correlation of 0.9999. The UV method demonstrated an improved precision compared to the bioassay method (1.0 versus 2.4%). The average recovery, 99.8 and 100.9%, was suitable in both methods. The results obtained by these 2 methods were compared with those of a high-performance liquid chromatography (HPLC) method published previously, and no evidence of significant difference was observed. The proposed methods are appropriate for the determination of voriconazole in tablets and can be used in routine quality control.Journal of AOAC International 06/2006; 89(4):960-965. · 1.20 Impact Factor -
Article: Microbiological assay for the determination of meropenem in pharmaceutical dosage form.
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ABSTRACT: Meropenem is a highly active carbapenem antibiotic used in the treatment of a wide range of serious infections. The present work reports a microbiological assay, applying the cylinder-plate method, for the determination of meropenem in powder for injection. The validation method yielded good results and included linearity, precision, accuracy and specificity. The assay is based on the inhibitory effect of meropenem upon the strain of Micrococcus luteus ATCC 9341 used as the test microorganism. The results of assay were treated statistically by analysis of variance (ANOVA) and were found to be linear (r=0.9999) in the range of 1.5-6.0 microg ml(-1), precise (intra-assay: R.S.D.=0.29; inter-assay: R.S.D.=0.94) and accurate. A preliminary stability study of meropenem was performed to show that the microbiological assay is specific for the determination of meropenem in the presence of its degradation products. The degraded samples were also analysed by the HPLC method. The proposed method allows the quantitation of meropenem in pharmaceutical dosage form and can be used for the drug analysis in routine quality control.Journal of Pharmaceutical and Biomedical Analysis 05/2005; 37(4):649-53. · 2.97 Impact Factor -
Article: Comparison of capillary electrophoresis and reversed-phase liquid chromatography methodologies for determination of diazepam in pharmaceutical tablets.
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ABSTRACT: Two novel analytical methodologies using capillary electrophoresis (CE) and reversed-phase high-performance liquid chromatography (RP-HPLC) for the determination of diazepam in commercial and simulated tablet formulations were developed and compared. The CE analysis was carried out in a bare fused-silica capillary with 75 microm i.d. and total length of 50 cm (28 cm to the detector) with a buffer solution containing 20 mmol L(-1) sodium tetraborate and 20 mmolL(-1) sodium dodecylsulfate (SDS), pH 9.23. The applied voltage was 20 kV and bromazepam was used as internal standard (IS). The RP-HPLC analysis was carried out in a LiChrospher((R)) 100 RP-18 (5 microm) column with a mobile phase constituted of methanol, acetonitrile and water (45:25:30) with a flow rate of 0.8 mL/min, using acetaminophen as IS. In both cases, detection was carried out by ultraviolet (UV) absorption at 242 nm. Under the optimized conditions, the CE retention times for the standard diazepam and bromazepam (IS) were 4.08 and 3.43 min, respectively, and the retention times of the RP-HPLC analysis for the standard diazepam and acetaminophen (IS) were 4.86 and 1.58 min, respectively. The resolution and efficiency for CE were 7.4 and 1.18 x 10(5)plates/m and for RP-HPLC, 7.5 and 1.76 x 10(4) plates/m. Analytical curves of peak area versus concentration presented correlation coefficients of 0.9996 for CE and 0.9994 for RP-HPLC. The limits of detection (LOD) and quantitation (LOQ) were 4.24 and 12.85 microg/mL for CE and 1.44 and 4.36 microg/mL for RP-HPLC. Relative standard deviations (R.S.D.) were 1.62 and 0.98% for CE and RP-HPLC, respectively. The percentage recovery determined with CE was 100.27+/-1.25 and with RP-HPLC was 101.12+/-2.48. Although both methodologies were shown to be suitable for the determination of diazepam in tablets, performing in a similar manner with regards to several aspects (linearity, recovery and specificity), CE provided a faster analysis and column efficiency whereas RP-HPLC presented a superior repeatability and sensitivity.Journal of Pharmaceutical and Biomedical Analysis 03/2005; 37(2):273-9. · 2.97 Impact Factor -
Article: Development and validation of dissolution tests for fexofenadine hydrochloride capsules and coated tablets.
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ABSTRACT: This study describes the development and validation of dissolution tests for fexofenadine hydrochloride capsules and coated tablets using an HPLC method. The appropriate conditions were determinate after testing sink conditions, dissolution medium, and agitation intensity. The apparatus, paddle and basket, were applied to tablets and capsules, respectively. Fexofenadine hydrochloride capsules, products A and B, and coated tablets, products A, B and C were evaluated. The best dissolution conditions tested, for the products in each respective pharmaceutical dosage form were applied to evaluate the dissolution profiles. The parameters of difference factor, similar factor, and dissolution efficacy were employed. Optimal conditions to carry out the dissolution tests were 900 ml of 0.01 M hydrochloric acid as dissolution medium, basket at 100 rotation per minute (rpm) stirring speed for capsules and paddle at 75 rpm for tablets. The dissolution profiles for tablets products A, B, and C and for capsules products A and B were not similar. The developed and validated dissolution tests satisfactorily describes the time-course of the drug release. The obtained results provided adequate dissolution profiles. The HPLC method was validated to quantify fexofenadine capsules and coated tablets from the dissolution tests.Journal of pharmacy & pharmaceutical sciences: a publication of the Canadian Society for Pharmaceutical Sciences, Societe canadienne des sciences pharmaceutiques 02/2005; 8(2):289-98. · 1.65 Impact Factor -
Article: Determination of rosiglitazone in coated tablets by MEKC and HPLC methods.
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ABSTRACT: Micellar electrokinetic chromatographic (MEKC) and high-performance liquid chromatographic (HPLC) methods were developed and subsequently validated for the determination of rosiglitazone (RSG) in coated tablet, a potent new oral antihyperglicemic agent. The electrophoretic separation was performed in a fused-silica capillary of total length 48.0 cm (effective length 39.5 cm, 75 microm i.d.) using 10 mM sodium tetraborate buffer (pH 9.0) containing 30 mM sodium dodecyl sulfate (SDS) as the background electrolyte (BGE). The separating voltage used was of 20 kV at 25 degrees C and the diode array detector was set at 247 nm. The MEKC method was compared with HPLC method using a RP-18 column (125 x 4.0mm i.d.) eluted with a mobile phase consisting of mixture of 25 mM potassium dihydrogen phosphate buffer and acetonitrile (55:45, v/v), adjusting the pH to 6.2 with dilute potassium hydroxide. Statistical analysis by Student's t-test showed no significant differences between the results obtained by two methods. The results indicated that MEKC can be used an alternative method to HPLC for the determination of rosiglitazone in pharmaceutical dosage form.Journal of Pharmaceutical and Biomedical Analysis 12/2004; 36(4):909-13. · 2.97 Impact Factor -
Article: Validation of HPLC and UV spectrophotometric methods for the determination of meropenem in pharmaceutical dosage form.
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ABSTRACT: A high-performance liquid chromatographic method and a UV spectrophotometric method for the quantitative determination of meropenem, a highly active carbapenem antibiotic, in powder for injection were developed in present work. The parameters linearity, precision, accuracy, specificity, robustness, limit of detection and limit of quantitation were studied according to International Conference on Harmonization guidelines. Chromatography was carried out by reversed-phase technique on an RP-18 column with a mobile phase composed of 30 mM monobasic phosphate buffer and acetonitrile (90:10; v/v), adjusted to pH 3.0 with orthophosphoric acid. The UV spectrophotometric method was performed at 298 nm. The samples were prepared in water and the stability of meropenem in aqueous solution at 4 and 25 degrees C was studied. The results were satisfactory with good stability after 24 h at 4 degrees C. Statistical analysis by Student's t-test showed no significant difference between the results obtained by the two methods. The proposed methods are highly sensitive, precise and accurate and can be used for the reliable quantitation of meropenem in pharmaceutical dosage form.Journal of Pharmaceutical and Biomedical Analysis 01/2004; 33(5):947-54. · 2.97 Impact Factor -
Article: Determination of cephalexin in oral suspensions by micellar electrokinetic chromatography.
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ABSTRACT: A simple and efficient micellar capillary electrophoresis method for the analysis of cephalexin in oral suspensions is described. The analysis was carried out in a bare silica capillary with 75 microm i.d. and total length of 50 cm (28 cm to the detector) with a buffer solution containing 20 mM sodium tetraborate, 20 mM sodium dodecyl sulfate, and 0.1% laurylpolyoxiethylenic ether. The applied voltage was 15 kV. Detection was achieved by ultraviolet absorption at 210 nm. The calibration curve was linear within the concentration range from 40.0 to 120 microg/mL with a correlation coefficient of 0.9998. The percentage recovery was found to be 100.09 +/- 0.56. The method showed good selectivity and resolution of the drug impurities, and was found suitable to study cephalexin stability in pharmaceutical preparations.Journal of capillary electrophoresis and microchip technology. 02/2002; 7(3-4):81-6. -
Article: Development and validation of a liquid chromatographic method for fexofenadine hydrochloride in capsules.
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ABSTRACT: This paper describes the development and validation of a new, simple, fast, and sensitive liquid chromatographic method for the determination of the antihistamine fexofenadine. Although widely used in the treatment of allergic diseases, fexofenadine is not listed in any pharmacopeia, and there are few methods in the literature for its quantitation in pharmaceutical dosage forms. In this work, a LiChrospher 100 RP-18 (250 x 4.0 mm, 5 microm) column was used as the stationary phase, and acetonitrile-5mM ammonium acetate buffer (50 + 50, v/v) at pH 3.2 was the mobile phase. Through the evaluation of the analytical parameters, it was shown that the method is linear (r = 0.9999) at concentrations ranging from 20.0 to 80.0 microg/mL, precise (intraday relative standard deviation [RSD] values = 0.85, 0.40, and 0.81%; interday RSD = 0.77%), accurate (mean recovery = 99.05%), specific, and robust. The detection and quantitation limits are 0.3409 and 1.033 microg/mL, respectively. These low values show the good sensitivity of the proposed method.Journal of AOAC International 87(5):1093-7. · 1.20 Impact Factor
Top co-authors
Top Journals
Institutions
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2002–2011
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Universidade Federal do Rio Grande do Sul
- Faculdade de Farmácia
Porto Alegre, Estado do Rio Grande do Sul, Brazil
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2005
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Universidade de São Paulo
- Departamento de Farmácia (FBF) (Sao Paulo)
Ribeirão Preto, Estado de Sao Paulo, Brazil
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