iTraq&TMT Labeling Technology

  • Quantitative Proteomics is the accurate identification and quantification of all proteins expressed in a genome or all proteins in a complex mixed system. It can be used to screen and find differentially expressed proteins between samples caused by any factor, combined with bioinformatics to reveal the physiological and pathological functions of cells, and also to qualitatively and quantitatively analyze certain key proteins.


    The iTRAQ (isobaric tags for relative and absolute quantitation) technique is a relative and absolute quantification technique for in vitro isotope labeling developed by AB SCIEX. This technology uses a variety of isotope reagents to label the N-terminal or lysine side chain groups of protein peptides. The high-precision mass spectrometer can be used to analyze the protein expression levels of up to 8 samples simultaneously. This is a quantitative proteome in recent years. Learn common high-throughput screening techniques. The iTRAQ Labeling technology uses four or eight isotopically encoded tags to specifically compare the relative or absolute levels of protein in four or eight different samples by specifically labeling the amino group of the polypeptide followed by tandem mass spectrometry.



    TMT Labeling Isobaric Chemical Labeling is a powerful tool for the simultaneous identification and quantification of proteins in different samples by tandem mass spectrometry. These tags are small chemical molecules of the same structure that are capable of covalently binding to the free amino terminus of the lysine residues of the protein and polypeptide, thereby enabling labeling of multiple polypeptides in the sample. In MS/MS analysis, each isobaric label produces a unique ion map that can be quantified using this label. In the first MS analysis, the labeled peptides were indistinguishable from each other; however, in tandem MS mode, the peptides were separated and fragmented, and each label produced a unique reporter ion. Proteins can be quantified by comparing the intensities of the six reporter ions in the MS/MS spectrum. The TMT reagent consists of three parts: a mass reporter group, a mass normalization group, and an amino reactive group. The mass reporting group has 10 different molecular weights, and the mass normalization group also has 10 different molecular weights. It can be matched with different reporter groups to ensure that the same peptides from different sources are identical in the first-order mass spectrum. The mass-to-charge ratio; the amino reactive group can be covalently linked to the N-terminus of the peptide and the amino group of the lysine side chain to link the peptide.



    Technical characteristics:


    Quantitative accuracy: up to 8 samples in parallel for each group, marking efficiency up to 97%, reducing sample processing and experimental errors caused by different groups of machines.


    High-efficiency sample separation: SCX-HPLC separation for automated operation.

    High identification rate: The system comprehensively studies as many proteins as possible in tissues or cells, and can identify up to 6,000 proteins.


    Wide range of applications: no species-specific limitations, theoretically applicable to all species.


    Excellent instrument performance: Based on high resolution (greater than 105), high quality accuracy (less than 1ppm) mass spectrometry platform, more accurate results can be obtained.