Publications by authors named "Katarína Reiffová"

5 Publications

  • Page 1 of 1

A new HPLC-MS/MS analytical method for quantification of tazobactam, piperacillin, and meropenem in human plasma.

J Sep Sci 2021 May 14. Epub 2021 May 14.

ELBLAB GmbH Zentrum für Labor Medizin Meißen Riesa Radebeul, Weinbergstraße 8, Riesa, Germany.

A simple and fast high-performance liquid chromatography with tandem mass spectrometry method for quantification of tazobactam, piperacillin, and meropenem in human plasma has been developed and validated. Simple sample preparation with a volume of 10 μL was done by protein precipitation with a mixture of methanol-acetonitrile-water (6:2:2, v/v/v). Chromatographic separation was achieved on a Luna column with a precolumn security guard by gradient elution using a mobile phase consisting of water with the addition of 0.1% formic acid (component A) and mixture methanol-acetonitrile (8:2, v/v) with the addition of 0.1% formic acid (component B). The run time was 2.7 min. The lower limits of detection and lower limits of quantification were for piperacillin 0.03 and 0.1 mg/L, for meropenem 0.04 and 0.2 mg/L and for tazobactam 0.16 and 0.5 mg/L. The validated method was used for therapeutic monitoring of tazobactam, piperacillin, and meropenem in samples of patients treated in the intensive care unit.
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http://dx.doi.org/10.1002/jssc.202100067DOI Listing
May 2021

A new HPLC-MS/MS method for simultaneous determination of Cyclosporine A, Tacrolimus, Sirolimus and Everolimus for routine therapeutic drug monitoring.

J Chromatogr B Analyt Technol Biomed Life Sci 2019 Oct 20;1128:121772. Epub 2019 Aug 20.

ELBLAB GmbH Zentrum für Labor Medizin Meißen Riesa Radebeul, Weinbergstraße 8, 01589 Riesa, Germany.

A rapid, simple and robust HPLC-MS/MS method for simultaneous determination of immunosuppressants Cyclosporine A, Tacrolimus, Sirolimus and Everolimus has been developed and validated. Sample of whole blood with volume of 50 μL was prepared by a protein precipitation with methanol and 0.5 mol. L ZnSO. Chromatographic separation was achieved on a Phenyl-Hexyl column by a gradient elution using 20 mmol.L ammonium formate/0.1% (v/v) formic acid in water (mobile phase A) and 20 mmol.L ammonium formate/0.1% (v/v) formic acid in methanol (mobile phase B) with flow rate 1 mL.min. The run time was 3.5 min. Electrospray ionization and multiple reaction monitoring was used. The lower limit of quantification (LLOQ) was set at 0.5 μg.L for Tacrolimus, Sirolimus and Everolimus and 5 μg.L for Cyclosporine A. The method demonstrated adequate accuracy and precision with sufficient linearity range.
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http://dx.doi.org/10.1016/j.jchromb.2019.121772DOI Listing
October 2019

Thin-Layer Chromatography: an Efficient Technique for the Optimization of Dispersive Liquid-Liquid Microextraction.

Acta Chim Slov 2018 Jun;65(2):388-393

Thin-layer chromatography (TLC) is an often omitted analytical technique due to its lower sensitivity and separation capacity. Even in the era of high-performance liquid chromatography (HPLC), thin-layer chromatography still offers many advantages, such as simplicity, rapidity, and cost-effectiveness, which predict TLC to be the first-choice method for the laborious optimization process requiring analysis of numerous samples. In this work, a thin-layer chromatography method with chemical and densitometric detection was used to optimize a dispersive liquid-liquid microextraction (DLLME) process for the extraction and preconcentration of estradiol in human urine. The chromatographic system consisted of silica gel plates as the stationary phase and toluene-ethanol (9:1; v/v) mixture as the developing solvent. The plates were dyed with 10% phosphomolybdic acid reagent and sequentially evaluated densitometrically at λ = 430 nm. In the context of DLLME optimization, parameters including the type and volume of extraction and dispersive solvents, centrifugation, salt addition and extraction time, were studied. The proposed DLLME-TLC method was successfully applied to the determination of estradiol in real human urine samples.
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http://dx.doi.org/10.17344/acsi.2017.4108DOI Listing
June 2018

Dispersive liquid-liquid microextraction as an effective preanalytical step for the determination of estradiol in human urine.

J Sep Sci 2017 Jun 11;40(12):2620-2628. Epub 2017 May 11.

Department of Analytical Chemistry, Faculty of Science, Pavol Jozef Šafárik University in Košice, Košice, Slovakia.

In this work, a fast and effective dispersive liquid-liquid microextraction was developed for the isolation and preconcentration of free 17 β-estradiol, the main human estrogen, from real human urine samples. To optimize the extraction technique, few important parameters such as type and volume of extraction and dispersive solvents, centrifugation conditions, effect of salt addition, and extraction time were studied. Optimal conditions were obtained when injecting 600 μL mixture of tetrachloromethane as extraction solvent and ethanol as dispersive solvent (1:5, v/v) into 2 mL of urine containing 8% NaCl and following centrifugation at 10 000 rpm, thus reaching enrichment factor 28 and extraction recovery 98% for estradiol. Procedure was evaluated by means of high-performance liquid chromatography with UV detection (λ = 280 nm) using a C-18 column and methanol/water (60:40, v/v) as the mobile phase. The method was linear within the concentration range 1.0-250.0 mg/L (r = 0.9997) and provided a limit of detection of 0.25 mg/L. The proposed method was applied to the determination of free estradiol in real human pregnancy urine.
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http://dx.doi.org/10.1002/jssc.201700123DOI Listing
June 2017

Thin-layer chromatography analysis of fructooligosaccharides in biological samples.

J Chromatogr A 2006 Mar 7;1110(1-2):214-21. Epub 2006 Feb 7.

University of P.J. Safárik, Faculty of Natural Sciences, Institute of Chemistry Sciences, Moyzesova 11, 040 01 Kosice, Slovak Republic.

This study presents the application of a rapid, simple and inexpensive thin-layer chromatography (TLC) for the analysis of fructooligosaccharides (FOSs) as feed additives (prebiotics) in complicated biological samples with minimal pre-treatment. Prebiotics have been monitored in different parts of the intestinal tract (jejunum, ileum and colon) of monogastric animals to which commercially available dietetic products containing fructooligosaccharides Raftifeed IPX, Raftilose and polysaccharide maltodextrin have been added into the feed. Thereby it contributes to a clarification of fructooligosaccharides and polysaccharides transformation in the digestive system. Chromatographic separation has been studied on different chromatographic systems (stationary and mobile phases). Optimal separation of fructooligosaccharides in dietetic products as well as in the samples from intestinal tract of monogastric animals has been achieved on glass-backed precoated silica gel layers impregnated with sodium acetate. The layers were developed with butanol-ethanol-water (5:3:2, v/v) in a vertical trough glass chamber with mobile phase vapour saturation. The visualisation of FOSs on chromatograms was performed with mixture of diphenylamine-aniline-phosphoric acid in acetone as primary detection reagent. Coloured spots of FOSs (blue-pink spots) on chromatograms have also been detected by reflectance densitometry at wavelength lambda=370nm. Simultaneously, the concentration of acetic acid, which is one of FOSs fermentation product, was monitored in the intestinal contents from jejunum, ileum and colon by capillary isotachophoresis.
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http://dx.doi.org/10.1016/j.chroma.2006.01.039DOI Listing
March 2006