In analytical chemistry, a tandem mass tag (TMT) is a chemical label that facilitates sample multiplexing in mass spectrometry (MS)-based quantification and identification of biological macromolecules such as proteins, peptides and nucleic acids.
[1][2] Despite these complications, TMT-based proteomics has been shown to afford higher precision than label-free quantification.
[3] In addition to aiding in protein quantification, TMT tags can also increase the detection sensitivity of certain highly hydrophilic analytes, such as phosphopeptides, in RPLC-MS analyses.
A mathematically rigorous approach called BACIQ, that integrates peptide intensities and peptide-measurement agreement into confidence intervals for protein ratios has emerged.
[8] The TKO standard can be used to assess interference [9][non-primary source needed] TMT tags are commonly used to label samples of equal abundance.