0000000000590721

AUTHOR

Luisa Gallo Martinez

showing 3 related works from this author

New spectrophotometric procedure for determining cefotaxime based on derivatization with 1,2-naphthoquinone-4-sulphonate into solid-phase extraction …

1998

Cefotaxime was derivatised with 1,2-naphthoquinone-4-sulphonate (NQS), extracted into solid-phase cartridges (C18) and detected using a UV-visible detection system. Optimum conditions for this new procedure were: hydrogencarbonate-carbonate buffer, pH 10.5, 5-min reaction time at 25 degrees C and an NQS concentration of 7.1x10(-3) mol l(-1). The accuracy and the precision of the liquid-solid procedure were tested. The procedure was used to measure cefotaxime in pharmaceutical and urine samples. The results obtained were contrasted with those reported for a HPLC method for urine samples. The generalized H-point standard additions method was used to measure cefotaxime in urine samples.

AdultCefotaximeChromatographyNQSGeneral ChemistryUrineCefotaximeHigh-performance liquid chromatographySensitivity and SpecificityCephalosporinschemistry.chemical_compoundchemistryPharmaceutical PreparationsSpectrophotometryStandard additionmedicineHumansIndicators and ReagentsSolid phase extractionDerivatizationChromatography High Pressure LiquidAntibacterial agentmedicine.drugNaphthoquinonesJournal of chromatography. B, Biomedical sciences and applications
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Comparison of several methods used for the determination of cephalosporins. Analysis of cephalexin in pharmaceutical samples

2002

The precision of UV absorbance of intact and acid degraded cephalosporins, ninhydrin, high performance liquid chromatography and iodometric methods used for analysis of cefoxitin, cefotaxime, cephazolin and cephalexin were compared. To obtain the calibration graphs the analytical signal used were: absorbance, first derivative absorbance, second derivative absorbance and H-point Standard Additions Method by using absorbance values at two selected wavelengths as analytical signal. These methods and calibration graphs were also used for the determination of cephalexin in pharmaceutical samples.

Clinical BiochemistryPharmaceutical ScienceCapsulesHigh-performance liquid chromatographyAnalytical ChemistryAbsorbancechemistry.chemical_compoundIodometrySpectrophotometryDrug Discoverypolycyclic compoundsmedicineChromatography High Pressure LiquidSpectroscopyAntibacterial agentSecond derivativeCephalexinChromatographymedicine.diagnostic_testChemistrydigestive oral and skin physiologyTitrimetryNinhydrinCephalosporinsSolutionsStandard additionNinhydrinIndicators and ReagentsSpectrophotometry UltravioletJournal of Pharmaceutical and Biomedical Analysis
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Improved Solid Phase Extraction Procedure for Assay of Cephalosporins in Human Urine Samples

1998

Abstract Solid phase extraction technique has been evaluated for the treatment of urine samples in the analysis of cephalosporins before injection into an HP-Hypersil ODS-C18 column. Cephalexin, cefotaxime, cefazolin, cefuroxime, and cefoxitin were tested with seven different reversed-phase extraction column cartridges and the obtained urine extracts were not clean. However, 3M Empore extraction disk cartridges packed with octadecyl (C18) bonded silica provided clean extracts with a single extraction. The recoveries of the five cephalosporins ranged from 56 to 60 % in the 1.25–500 g/mL concentration range. The assay was accurate, precise, and adequate for testing the drug content in urine s…

Detection limitChromatographyChemistryClinical BiochemistryExtraction (chemistry)Pharmaceutical ScienceUrineBiochemistryHigh-performance liquid chromatographyAnalytical ChemistryCefalexinmedicineSolid phase extractionCefuroximeAntibacterial agentmedicine.drugJournal of Liquid Chromatography & Related Technologies
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