Fabrication and Application of Isotopically Labelled Gold Arrays for Multiplexed Peptide Analysis.

A new array-based technology for the simultaneous capture, chemical labelling and mass spectrometry analysis of peptides is presented. Isotopically labelled self-assembled monolayer (SAM) gold arrays are constructed and used simultaneously to capture and label a range of peptides. The array-immobilised, labelled peptides were released by MALDI ablation, analysed by MALDI mass spectrometry and readily identified as labelled peptides from their characteristic isotope pattern. This new solid-phase array platform has the advantage of minimal sample manipulation and is suitable for multiple analyses of single protein digests on a single MALDI target plate.

Evaluation of a solid-supported tagging strategy for mass spectrometric analysis of peptides.

We have explored two divinylbenzene cross-linked polystyrene supports for use in a solid-supported N-terminal peptide tagging strategy. Resin-bound tags designed to be cleaved in a single step at the N-terminus of peptides have been devised and explored as peptide N-terminal tagging reagents (constructs) for subsequent mass spectrometric analysis. While the brominated tagging approach shows promise, the use of these specific solid supports has drawbacks, in terms of tagging reaction scale, for real applications in proteomics.