title: Determination of homocysteine thiolactone in urine by field amplified sample injection and sweeping MEKC method with UV detection.
abstract: Homocysteine thiolactone (Hcy-thiolactone), an intramolecular thioester, easily acylates free-amino groups in proteins, which impairs or alters the protein's biological function. Here, we describe new capillary electrophoresis assay for the determination of Hcy-thiolactone in human urine based on a field amplified sample injection and sweeping MEKC with UV detection. The two steps procedure relies on sample liquid-liquid extraction followed by CE separation and UV detection at 240nm. The Hcy-thiolactone standard added to the urine before the extraction step shows that the response of the detector is linear within the range studied, from 0.1 to 1μmolL(-1) urine. The intra- and interday precision and recovery were 3.2-14.4% (average 5.1% and 9.3%) and 92.5-112.6% (average 99.8% and 99.1%), respectively. The lower limit of quantification was 0.09nmol Hcy-thiolactone in 1mL of urine. The proposed method was applied for the analysis of 15 urine samples donated by apparently healthy volunteers. The average concentration of the analyte was 0.170±0.029μmolL(-1).
authors.affiliation: University of Łódź, Faculty of Chemistry, Department of Environmental Chemistry, 163 Pomorska Str., 90-236 Łódź, Poland.
authors.forename: Paulina
authors.initials: P
authors.lastname: Furmaniak
authors.affiliation: University of Łódź, Faculty of Chemistry, Department of Environmental Chemistry, 163 Pomorska Str., 90-236 Łódź, Poland. Electronic address: pakuba@uni.lodz.pl.
authors.forename: Paweł
authors.initials: P
authors.lastname: Kubalczyk
authors.affiliation: University of Łódź, Faculty of Chemistry, Department of Environmental Chemistry, 163 Pomorska Str., 90-236 Łódź, Poland. Electronic address: glowar@uni.lodz.pl.
authors.forename: Rafał
authors.initials: R
authors.lastname: Głowacki
mesh_terms: D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods; D006710:Homocysteine / Q000031:analogs & derivatives* / Q000652:urine; D006801:Humans; D057230:Limit of Detection; D059625:Liquid-Liquid Extraction; D015203:Reproducibility of Results
chemical_list: D006710:Homocysteine; C007957:homocysteine thiolactone
keywords: Capillary electrophoresis; Homocysteine thiolactone; Ultraviolet detection, Urine