ankara univ vet fak derg Ankara Üniversitesi Veteriner Fakültesi Dergisi 1300-0861 1308-2817 Ankara University 10.33988/auvfd.538782 Veterinary Surgery Veteriner Cerrahi Determination and stability of some international screening limited drugs in equine blood by LC-MS/MS https://orcid.org/0000-0002-1269-8114 Göktaş Eylem Funda https://orcid.org/0000-0002-0339-0353 Kabil Erol https://orcid.org/0000-0001-9872-1882 Güneş Ertuğrul https://orcid.org/0000-0001-8970-6883 Korkmaz Serol https://orcid.org/0000-0003-2048-9854 Kadıoğlu Tuba Asena https://orcid.org/0000-0001-9527-4730 Kurt Cücü Ayşen 09 09 2019 66 4 363 372 03 13 2019 07 10 2019 Copyright © 1954, Ankara Üniversitesi Veteriner Fakültesi Dergisi 1954 Ankara Üniversitesi Veteriner Fakültesi Dergisi

Stability of someinternational screening limited therapeutic substances for doping control inequine blood has been investigated with a validated method by using LC-MS/MSafter chemical hydrolysis with orthophosphoric acid. Whole blood samples were extractedwith a WAX cartridge on auto-SPE. Stability test of the drug substancesperformed at the same time in working solution and matrix at +4°C, -20°C, +20°Cin dark and +20°C in light conditions for 1, 2, 3 and 4 weeks. For short-timestability, the effects of 6 h storage at +55°C was also investigated. Repeated data were statistically analyzed with ANOVA.All substances in working solution were stable at -20°C and +4°C. In the bloodmatrix, higher temperatures (+20°C) in light and dark caused degradation ofsubstances at the end of four weeks and short-term study (P< 0.05). Inconclusion, these international screening limited substances in blood matrixcould be unstable related to temperature and storage time, although in workingsolution they could be mostly stable in various temperatures for four weeks.

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