Enantiomeric methadone quantitation on real post-mortem dried matrix spots samples: Comparison of liquid chromatography and supercritical fluid chromatography coupled to mass spectrometry

This study describes two bioanalytical methods for the quantitation of methadone enantiomers in dried matrix spots using high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) and supercritical (HPSFC-MS/MS). Dried were obtained by spotting 10 µL each sample fluid on a Whatman paper. Methadone its main metabolite, EDDP, extracted with 100 methanol subsequently injected into LC-MS/MS SFC-MS/MS systems. Enantiomeric separation was achieved AGP-column LC conditions Chiralpak IH-3 SFC. The fully validated 93 post-mortem samples analysed both analytical methods. Results from validation parameters results all compared significant spearman correlation rs = 0.9978 R-methadone 0.9981 S-methadone. method provided better terms uncertainty, retention factor resolution, whereas SFC provides sensitivity, lower LOD. Median R-/S-methadone ratio peripheral blood found equal 1.60 (N 32), varying 0.79 4.23. reported values good agreement previously published results. Based here, can be considered reliable alternative widely used bioanalysis should evaluated other Both easily quickly toxicological routine analysis human fluids matrices, even if considering that polysaccharide coated column does not allow enantiomeric EDDP separation.