LC-MS determination of catecholamines and related metabolites in red deer urine and hair extracted using magnetic multi-walled carbon nanotube poly(styrene-co-divinylbenzene) composite

Abstract A novel analytical methodology for the determination and extraction of catecholamines (dopamine, epinephrine and norepinephrine) and their metabolites DL-3,4-dihydroxyphenyl glycol and DL-3,4-dihydroxymandelic acid by LC-MS is here developed and validated for application to human and animal urine and hair samples. The method is based on the preliminary extraction of analytes by a magnetic multi-walled carbon nanotube poly(styrene-co-divinylbenzene) composite. This is followed by a 90%. Accuracy values comprised the range 79.5–109.5% when the analytes were extracted from deer urine samples using the selected MMWCNT-poly(STY-DVB) sorbent. This methodology was applied to real red deer urine and hair samples, the resulting concentrations within range from 0.05 to 0.5 µg mL-1 for norepinephrine and from 1.0 to 44.5 µg mL-1 for its metabolite 3,4-dihydroxyphenyl glycol. Analyses of red deer hair resulted in high amounts of 3,4-dihydroxyphenyl glycol (0.9–266.9 µg mL-1).