Ricerc@Sapienza

Short peptides are important compounds in a variety of fields, including food and nutraceutical applications, but also biomarker discovery, bioactive peptide discovery and peptide drug separation. Despite the importance of short peptides, they are currently less studied than other peptides because of the lack of dedicated methods for their characterization. The method described in this paper comprises a combination of strategies to tackle the main limitations in short peptide analysis.

The combination of an efficient chromatographic separation with post-column addition of a supercharging agent was evaluated for the determination of small peptides. The procedure takes advantage of porous graphitic carbon (PGC) ability in retaining very polar and ionic molecules to overstep the poor retention of small peptides on conventional reversed phase (RP) columns. The method was developed specifically for the most hydrophilic di-, tri- and tetrapeptides, which are not identified in ordinary peptidomics experiments.

Short peptides, namely di- tri- and tetra peptides, have been proven to play an important diagnostic role in several diseases. Therefore, the development of an analytical approach for their detection and identification is nowadays an important research goal. This paper describes an analytical procedure able to overcome the issues of short peptide isolation, clean-up and identification in plasma samples. Four different protocols were compared and tested to maximize both recovery and total number of identifications of short circulating plasma endogenous peptides.