on 09-14-201203:22 AM - edited on 10-15-202108:03 AM by Closed Account
Thomas A, Walpurgis K, Krug O, Schänzer W, Thevis M. J Chromatogr A. 2012 Oct 12;1259:251-7. In the present study, a screening assay was developed comprising 11 prohibited peptides (<1.5kDa) that are sufficiently purified from urine using weak cation exchange with subsequent determination of all substances by means of nanoUHPLC separation coupled to high resolution tandem mass spectrometry. These peptides included Gonadorelin (LH-RH), Desmopressin and 9 growth hormone releasing peptides (GHRP-1, -2, -4, -5, -6, Hexarelin, Alexamorelin, Ipamorelin and a GHRP-2 metabolite); however, the procedure is expandable to further target analytes or metabolites. The method was validated with a main focus on qualitative result interpretation considering the parameters specificity, linearity (0-500pg/mL), recovery (45-95%), precision (<20% at 100pg/mL), limits of detection (2-10pg/mL), robustnesss and ion suppression. The proof-of-principle was shown by analysing excretion study urine samples for LHRH, Desmopressin and GHRP-2.