Target Discovery - Mass Defect Technology

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Mass Defect Technology

Mass Defect Technology refers to chemical tagging of biomolecules with a chemical compound that contains one or more elements with a substantial mass defect. Because the mass defect causes an element to be lighter in weight that its theoretical nuclear composition suggests, anything tagged with this element is shifted in the mass spectrum, away from untagged biomolecular species (which have near zero mass defects). As such, mass defect technology is broadly applicable to many aspects of biomolecular mass spectrometry and can be incorporated into a variety of mass spectrometric methods.

Learn more about the Mass Defect

Isotope-Differentiated Binding Energy Shift Tags

IDBEST™ allows tagged immunoaffinity-enriched biomarkers to be discriminated in the mass spectrometer from untagged antibodies or bait proteins used for the enrichment. In addition to the mass defect element, IDBEST™ tags also incorporate stable isotopes to create two chemically-identical, but isotopically-distinct versions of the same tag. This allows us to tag two patient samples with isotopically-distinct versions of the same tag and mix the tagged patient samples together before the affinity enrichment of the biomarker of interest. The resulting ratio between the amounts of light (healthy control sample} and heavy (diseased sample) is quantitatively determined as are any differences between peptides containing post-translational modifications.

The stable isotope pairing makes the assay quantitative. The mass defect element in the tag allows the biomarker of interest to be discriminated from other extraneous noise in the spectrum using TDI’s proprietary deconvolution software. IDBEST™ solves the sample complexity and dynamic range problems intrinsic to global proteomic methods.

Low abundance biomarkers are selectively enriched and can be seen in the mass spectrometer.
The sample entering the mass spectrometer is simplified so that the whole protein can be interrogated for isoforms.
Multiple biomarker "fishing expeditions” can be conducted on the same sample (i.e., the method is nondestructive of the sample).
By using affinity enrichment for the protein of interest, the time and cost of analysis is greatly reduced.

IDBEST™ Example