Reactive Components

(Picolyl-) Azides of fluorescent dyes can be used for the fluorescent labeling of terminal Alkyne and strained Alknye (e.g DBCO)-labeled molecules via Cu(I)-catalyzed Alknye-Azide (CUAAC) or Cu(I)-free strain-promoted Alkyne-Azide Click Chemistry (SPAAC) reaction, respectively.

Standard Dyes such as Cy3, Tamra or Texas Red have been thoroughly selected to cover the whole UV-Vis spectrum. Novel Alternative Dyes are available as well.

Table 1: Available (Picolyl-) Azide-containing Fluorescent Dyes

Alkyne-containing Fluorescent dyes can be used for the fluorescent labeling of Azide-tagged molecules via a Cu(I)-catalyzed Azide-Alkyne Click Chemistry reaction (CuAAC).

Standard Dyes (e.g. Cy3, Tamra or Texas Red) have been thoroughly selected to cover the whole UV-Vis spectrum.

Table 1: Available Alkyne-containing Fluorescent Dyes

Dibenzocyclooctyne (DBCO)^*-containing fluorescent dyes can be used for the fluorescent labeling of Azide-tagged biomolecules via Cu(I)-free strain-promoted Alkyne-Azide Click Chemistry (SPAAC). Both Standard Dyes (e.g. Cy3, Tamra or Texas Red) and novel Alternative Dyes have been thoroughly selected to cover the whole UV-Vis spectrum.

^*DBCO is also known as ADIBO (= Azadibenzocyclooctyne)

Table 1: Available DBCO-containing Fluorescent Dyes

Tetrazine-containing fluorescent dyes are suitable for fluorescent labeling of Cyclooctene-labeled molecules via Cu-free Click Chemistry. Both Standard Dyes (e.g. Cy3 or Tamra) and novel Alternative Dyes have been thoroughly selected to cover the whole UV-Vis spectrum.

Two Tetrazine versions with different reactivities and stability characteristics are available to meet specific application requirements. Tetrazine reagents are the ideal choice if a rapid reaction kinetic is the key aspect whereas 6-Methyl-Tetrazine reagents are ideally suited if an improved chemical stability is required¹.

Table 1: Available Tetrazine-containing Fluorescent Dyes

Selected References

[1] Karver et al. (2011) Synthesis and Evaluation of a Series of 1,2,4,5-Tetrazines for Bioorthogonal Conjugations. Am. Chem. Soc. 22:2263.

NHS Ester of Biotin enable Biotin labeling of proteins (e.g. antibodies) and any other primary amine-containing macromolecules. These biotinylated molecules are subsequently detected via fluoresecent or HRP-labeled streptavidin.

Binding of Biotin by avidin, streptavidin or NeutrAvidinTM is the strongest known biological interaction with a dissociation constant in the range of 10-15 M. The vitamin Biotin may be conjugated to many proteins without loss of their biological activity due to the small size of the biotin molecule.

Labeling of a molecule (e.g. a protein or nucleic acid) with biotin/desthiobiotin is routinely performed for its subsequent affinity purification via streptavidin agarose or detection with fluorescent or HRP-labeled streptavidin. Due to the extremely high affinity of biotin towards streptavidin (K_D = 10^-15 M), the biotinylated molecule/streptavidin-interaction is essentially irreversible under physiological conditions. Desthiobiotin however, binds less tightly to streptavidin (K_D = 10^-11 M) and desthiobiotinylated molecules are therefore easily eluted from the complex in the presence of excess Biotin.

Azides of biotinylation reagents can be used for the labeling of terminal Alkyne- and strained Alkyne (e.g. DBCO)-labeled biomolecules via Cu(I)-catalyzed Alknye-Azide (CUAAC) or Cu(I)-free strain-promoted Alkyne-Azide Click Chemistry (SPAAC) reaction, respectively.

A number of (desthio)biotinylation reagents with

• • different solubility characteristics (PEG-linker for increased molecule solubility)

• optimized streptavidin binding characteristics (different PEG-linker length)
• different cleavability characteristics (Diazo-linker for removal of the biotin moiety upon purification)

are available to fit specific application & molecule requirements.

Alkyne-containing (desthio) biotinylation reagents can be used for the labeling of Azide-tagged biomolecules via a Cu(I)-catalyzed Azide-Alkyne Click Chemistry reaction (CuAAC).

A number of (desthio) biotinylation reagents with

• • improved solubility & detection characteristics (PEG-linker for increased molecule solubility & optimal streptavidin binding)

• different cleavability characteristics (chemically or photocleavable linker)

are available to fit specific application & molecule requirements.

Dibenzocyclooctyne (DBCO)^*-containing (desthio) biotinylation reagents can be used for the labeling of Azide-tagged biomolecules via Cu(I)-free strain-promoted Alkyne-Azide Click Chemistry (SPAAC).

A number of (desthio) biotinylation reagents with

• • different solubility characteristics (PEG- and Sulfo-linker for increased molecule solubility)

• different cleavability characteristics (chemically or photocleavable linke)

are available to fit specific application & molecule requirements.

^*DBCO is also known as ADIBO (= Azadibenzocyclooctyne) or DIBAC (= Dibenzoazacyclooctyne)

Azide-containing bifunctional reagents are suitable for the introduction of

• a functional group to terminal Alkyne-tagged or strained Alkyne (e.g. DBCO)-tagged molecules via Cu(I)-catalyzed Alknye-Azide (CUAAC) or Cu(I)-free strain-promoted Alkyne-Azide Click Chemistry (SPAAC) reaction, respectively
• an Azide group to various targets e.g. via NHS Ester- or Maleimide-based chemistry

Table 1: Available Azide-containing Bifunctional Reagents

Alkyne-containing reagents can be used for the introduction of

• a functional group to Azide-labeled molecules via a Cu(I)-catalyzed Azide-Alkyne Click Chemistry reaction (CuAAC)
• an Alkyne group to various targets e.g. via NHS Ester- or Maleimide-based chemistry

Table 1: Available Alkyne-containing Bifunctional Reagents

Dibenzocyclooctyne (DBCO)^*-containing bifunctional reagents can be used for the introduction of

• a functional group to Azide-labeled molecules via Cu(I)-free strain-promoted Alkyne-Azide Click Chemistry (SPAAC)
• an DBCO group to various targets e.g. via NHS Ester- or Maleimide-based chemistry

^*DBCO is also known as ADIBO (= Azadibenzocyclooctyne) or DIBAC (= Dibenzoazacyclooctyne)

Table 1: Available DBCO-containing Bifunctional Reagents

Tetrazine-containing reagents are suitable for the introduction of

• a functional group (e.g. Amine or NHS Ester) to Cyclooctene-labeled molecules via Cu-free Click Chemistry
• an Tetrazine group to various targets e.g. via NHS Ester- or Maleimide-based chemistry

Two Tetrazine versions with different reactivities and stability characteristics are available to meet specific application requirements. Tetrazine reagents are the ideal choice if a rapid reaction kinetic is the key aspect whereas 6-Methyl-Tetrazine reagents are ideally suited if an improved chemical stability is required^[1].

Table 1: Available Tetrazine-containing Bifunctional Reagents

Selected References

[1] Karver et al. (2011) Synthesis and Evaluation of a Series of 1,2,4,5-Tetrazines for Bioorthogonal Conjugations. Am. Chem. Soc. 22:2263.

Trans-Cyclooctene-containing bifunctional reagents can be used for the introduction of

• a functional group (e.g. Amine or NHS Ester) to Tetrazine-labeled molecules via Cu-free Click Chemistry
• an Cyclooctene group to various targets e.g. via NHS Ester- or Maleimide-based chemistry

Table 1: Available Trans-Cyclooctene-containing Bifunctional Reagents

Selected References:

Selvaraj et al. (2013) trans-Cyclooctene – a stable voracious dienophile for bioorthogonal labeling. Current Opinion in Chemical Biology 17:753.