Dimethyl Labeling

The dimethyl labeling technique uses a reagent mixture (i.e., cyanoborohydride and formaldehyde in their unlabeled and stable isotope-labeled forms) to tag primary amines (e.g., ε-amino group of lysine) in analytes, such as peptides and metabolites. This is a fast, straightforward, and inexpensive approach to conduct 2- or 3-plex quantitative omic analyses of a variety of sample types (e.g., lysate, tissue). To facilitate reductive amination reactions in quantitative ome profiling (example provided in App Note 38), CIL is pleased to offer a variety of chemical tagging reagents and reagent sets (Dimethyl-2Plex and Dimethyl-3Plex).

➤ Stable Isotope Standards for Mass Spectrometry

Application Note
➤ Stable Isotope Dimethyl Labeling

Dimethyl Labeling Reagent Sets

Frequently Asked Questions

At what stage of a bottom-up proteomics experiment are the dimethyl labeling reagents inserted? The reductive methylation reagents (i.e., formaldehyde and cyanoborohydride) are typically added to peptides post-digestion.

Is reductive dimethylation limited to peptides? No. This tagging approach can be applied to metabolites as well for quantification of amine-containing metabolites in biological samples (see literature for example references).

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