ICAT reagents, Applied Biosystems' first foray into multiplexed LC/MS sample preparation, attach to cysteine residues. The new iTRAQ reagents are amine-specific and thus tag all peptides (not just those containing cysteine), thereby expanding proteome coverage.
Potential applications include membrane-protein studies, target-protein quantitation, and biomarker discovery and validation. Richard A. Caprioli, director, Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, recently purchased the kit. "It seems like a straightforward approach involving well-known tools put into a very nice package," he says. "I suspect Applied Biosystems did their homework, and I am hopeful that the reagents will work well."
- Emma Hitt