Publications by authors named "Bengt-Arne Persson"
Article Synopsis
- Researchers explored a chromatographic system using carbon dioxide and methanol to analyze metoprolol and similar amino alcohols, incorporating strong acids to enhance selectivity.
- Standard conditions involved a mix of methanol with a specific acid concentration and triethylamine, achieving significant resolution with trifluoroacetic acid over ethanesulfonic acid.
- The study found that structural variations near the nitrogen of amino alcohols significantly influenced selectivity, and the described method improves separation efficiency without changing the stationary phase.
In the course of development and validation of a gas chromatography-mass spectrometry (GC-MS) method for ramipril and its biologically active metabolite ramiprilat, evidence was found for an unknown interfering metabolite. Sample treatment included isolation from plasma or urine by solid-phase extraction, methylation with trimethylsilyldiazomethane and acylation with trifluoroacetic anhydride (TFAA). When liquid chromatography was used to fractionate plasma extracts prior to derivatization, the alkyl, acyl-derivative of ramipril was obtained from two separate LC fractions.
View Article and Find Full Text PDFDetermination of ximelagatran, an oral direct thrombin inhibitor, its active metabolite melagatran, and the intermediate metabolites, in biological samples by liquid chromatography-mass spectrometry.
J Chromatogr B Analyt Technol Biomed Life Sci
January 2003
Analytical methods for the determination of ximelagatran, an oral direct thrombin inhibitor, its active metabolite melagatran, and intermediate metabolites, melagatran hydroxyamidine and melagatran ethyl ester, in biological samples by liquid chromatography (LC) positive electrospray ionization mass spectrometry (MS) using selected reaction monitoring are described. Isolation from human plasma was achieved by solid-phase extraction on octylsilica. Analytes and isotope-labelled internal standards were separated by LC utilising a C(18) analytical column and a mobile phase comprising acetonitrile-4 mmol/l ammonium acetate (35:65, v/v) containing 0.
View Article and Find Full Text PDFDetermination of melagatran, a novel, direct thrombin inhibitor, in human plasma and urine by liquid chromatography-mass spectrometry.
J Chromatogr B Analyt Technol Biomed Life Sci
January 2002
Analytical methods for the determination of melagatran (H 319/68) in biological samples by liquid chromatography (LC)-positive electrospray ionization mass spectrometry using multiple reaction monitoring are described. Melagatran in plasma was isolated by solid-phase extraction on octylsilica, either in separate extraction tubes or in 96-well plates. Absolute recovery of melagatran from plasma was >92%.
View Article and Find Full Text PDFArticle Synopsis
- An analytical method was developed to determine the enantiomers of felodipine in human blood plasma, using toluene for extraction and a specific stationary phase for separation.
- The detection involved a post-column addition process that enabled sensitive measurement of the drug by electrospray ionization, with a racemic form used as an internal standard to improve accuracy.
- The method demonstrated high repeatability and precision, making it suitable for pharmacokinetic studies of felodipine after oral administration.