Rapid screening of polysaccharide based plasma volume expanders dextran and hydroxyethyl starch in human urine by liquid chromatography - tandem mass spectrometry

The increasing number of samples and target substances in doping control require continuously improved screening methods, combining high throughput analysis, simplified sample preparation, robustness and reliability. Hence, a rapid screening procedure based on liquid chromatography - electrospray ionisation - tandem mass spectrometry with in-source collision-induced dissociation was developed. The detection of the polysaccharide-based plasma volume expanders dextran and hydroxyethyl starch (HES) in human urine was established without further sample preparation. The in-source fragmentation strategy of the approach represented a valuable tool in the analysis of the polysaccharide-based compounds, allowing the use of tandem mass spectrometry. After direct injection of urine specimens, analytes were chromatographically separated on a monolithic reverse phase column utilizing gradient elution and detected via multiple reaction monitoring of diagnostic ions at detection limits of 10 µg/mL for HES and 30 µg/mL for dextran. Validation was performed regarding the parameters specificity, linearity, precision (8-18 %) and accuracy (77-105 %) and the method was applied to the investigation of approx. 400 doping control samples and 7 dextran and 2 hydroxyethyl starch post-administration samples. The approach demonstrated its capability as a rapid screening tool for the detection of dextran and hydroxyethyl starch and represents an alternative to existing screening procedures since time consuming hydrolysis or derivatisation steps were omitted. Verf.-Referat