LC-MS/MS analytical procedure to detect small peptides in biological samples:evaluation of different SPE extraction sorbents and protocols

Recently a wide variety of peptide hormones were included in the World Anti-Doping Agency list of prohibited substances and methods [1]. Traditionally, the analytical procedures used to detect macromolecules in the anti-doping field were based on immunological techniques. The increasing availability of recombinant peptides and other macromolecules with minimal differences in the molecular structure with respect to those produced endogenously has imposed the development of more selective techniques, mostly based on mass spectrometry. Several analytical procedures were already published to detect antidiuretic peptides [2-3], growth hormone releasing factors [4-5], ACTH and its analogues, IGF1 and its analogues and insulin analogues [6] in biological fluids (urine and blood). Here we present an analytical method for the combined screening of different small peptides, based on LC-MS/MS with SRM as acquisition mode after solid phase extraction.