AAT Bioquest

FastClick™ Digoxigenin (DIG) Azide


See also: Click Chemistry
Molecular weight
FastClick™ Digoxigenin (DIG) Azide contains both the CAG moiety of FastClick (for assisting click efficiency) and DIG hapten (as the detection tag) for developing DIG-based probes. It readily reacts with an alkyne-containing biomolecule under extremely mild conditions. DIG is a steroid found exclusively in the flowers and leaves of the plants Digitalis purpurea, Digitalis orientalis and Digitalis lanata. It is a commonly used hapten (a small molecule with high antigenicity) that finds utilities in biological detections similarly to other popular haptens such as 2,4-Dinitrophenol (DNP) and biotin. DIG conjugates and tags are widely used in fluorescence imaging, fluorescence in situ hybridization (FISH) and other nucleic acid detections. FastClick™ reagents have been developed by the scientists of AAT Bioquest for enhancing the yield and reaction speed of copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. They contain a copper-chelating ligand that significantly stabilizes the Cu(I) oxidation state and thus accelerates the click reaction. They do not require the use of an external copper-chelator (such as the common THPTA or BTTAA). The high concentration of copper chelators is known to have a detrimental effect on DNA/RNA, thus causing biocompatibility issues. The introduction of a copper-chelating moiety at the reporter molecule allows for a dramatic raise of the effective Cu(I) concentration at the reaction site and thus accelerates the reaction. Under extremely mild conditions the FastClick™ azides and alkynes react much faster in high yield compared to the corresponding conventional CuAAC reactions. Click chemistry was developed by K. Barry Sharpless as a robust and specific method of ligating two molecules together. Two important characteristics make click chemistry attractive for assembling biomolecules. First, click reactions are bio-orthogonal, thus the click chemistry-functionalized biomolecules would not react with the natural biomolecules that lack a clickable functional group. Second, the reactions proceed with ease under mild conditions, such as at room temperature and in aqueous media.


Common stock solution preparation

Table 1. Volume of DMSO needed to reconstitute specific mass of FastClick™ Digoxigenin (DIG) Azide to given concentration. Note that volume is only for preparing stock solution. Refer to sample experimental protocol for appropriate experimental/physiological buffers.

0.1 mg0.5 mg1 mg5 mg10 mg
1 mM129.202 µL646.012 µL1.292 mL6.46 mL12.92 mL
5 mM25.84 µL129.202 µL258.405 µL1.292 mL2.584 mL
10 mM12.92 µL64.601 µL129.202 µL646.012 µL1.292 mL

Molarity calculator

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View all 2 references: Citation Explorer
Analysis of a temperature-sensitive mutation in Uba1: Effects of the click reaction on subsequent immunolabeling of proteins involved in DNA replication.
Authors: Sugaya, Kimihiko and Ishihara, Yoshie and Inoue, Sonoe
Journal: FEBS open bio (2015): 167-74
Cell surface display yields evolvable, clickable antibody fragments.
Authors: Van Deventer, James A and Yuet, Kai P and Yoo, Tae Hyeon and Tirrell, David A
Journal: Chembiochem : a European journal of chemical biology (2014): 1777-81