Piotr Kowalski

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We prove that if G is an algebraic D-group (in the sense of Buium [B]) over a differentially closed field (K, ∂) of characteristic 0, then the first order structure consisting of G together with the algebraic D-subvarieties of G,G × G, . . ., has quantifier-elimination. In other words, the projection on Gn of a D-constructible subset of Gn+1 is(More)
A capillary electrophoresis (CE) and a reversed phase high-performance liquid chromatography (RP-HPLC) method with UV detection have been developed for florfenicol analysis in plasma samples. The suitabilities of both methods for quantitative determination of florfenicol were approved through validation specification, such as linearity, precision,(More)
A rapid and sensitive reversed-phase liquid chromatographic method (RP-LC) with UV detection has been developed for the determination of free cortisol, cortisone and corticosterone in human urine. The assay was performed after a solid-phase extraction procedure (SPE) with dexamethasone as the internal standard. Chromatographic separation was carried out on(More)
Two methods, capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC), for analysis of cetirizine dihydrochloride in small sample volumes of human plasma were compared. The CE and HPLC assays were developed and validated by analyzing a series of plasma samples containing cetirizine dihydrochloride in different concentrations using(More)
A capillary electrophoresis (CE) procedure has been developed for the determination of piracetam in human plasma. Analyses were performed on an uncoated silica capillary using borax buffer modified with the addition of alpha-cyclodextrin. The detection was UV, operated at 200 nm. The detection limit of the authentic samples was 1 microg/ml. The calibration(More)
Alkaloids are natural products of metabolism found mainly in plants. Their diversified pharmacological activities as medical agents and extensive occurrence in nutritional products demand the development of reliable and sensitive analytical tools. This review presents the developments in the field of electromigration techniques and specifically capillary(More)
  • P Kowalski
  • Journal of pharmaceutical and biomedical analysis
  • 2008
A capillary electrophoresis (CE) method with UV detection was developed for simultaneous identification and quantitation of three tetracyclines: tetracycline (TC), oxytetracycline (OTC) and doxycycline (DC) in fish muscle samples. It was developed by analyzing a series of fish tissue samples containing TCs in different concentrations. The CE method was(More)
The aim of the evaluation was to establish bioequivalence between two oral 3.0 g sachet forms of L-ornithine-L-aspartate (LOLA). It was designed as randomised, two-way crossover study with a 1-week washout interval. Blood samples were collected throughout a 12 h period after administration of reference and test product to 12 fasting healthy male volunteers.(More)