Rohan A. Thakur

This article examines the problem of dermorphin doping in horse racing and presents an effective method for its detection using LC–MS TQ.

This article introduces the advantages of accurate mass high-resolution mass spectrometry LC–MS (HRMS) coupled to the dried blood spot (DBS) technique for fast PK applications in a discovery environment. Compared with the established norm of plasma bioanalysis using triple quadrupoles, HRMS coupled to DBS is a viable alternative. The benefit is access to critical new information (HRMS bioanalysis) and significantly less stress on the animal (DBS), both factors that potentially improve the quality of early PK data.

In preclinical development, the absolute quantification of peptides in biological matrices becomes a challenge due to the limited availability of stable label internal standards and affinity-based cleanup. This puts a renewed emphasis on matrix effects, especially for the bioanalysis of hydrophobic peptides. While the impact of matrix effects has been studied for extensively singly charged small molecules, their effect on multiply charged compounds has yet to be characterized fully. This article discusses initial results from matrix effect experiments in relation to the bioanalysis of hydrophobic peptides and techniques used to minimize matrix effects.