Enhanced Diagnostic Tools
Probing by chemoselective ligation uses bioorthogonal reactions to cross link two
molecules without cross reactions with other biological functional groups. These
chemical reactions permit regioselective covalent attachment of oligonucleotides
with other biomolecules and permit the study of biomolecules real time in living
systems without interfering normal cellular functions. Bioorthogonal probe "click"
reactions are now widely used in chemical biology for many applications such as
activity-based protein profiling, monitoring cell proliferation, generating novel
enzyme inhibitors, and monitoring the synthesis of newly formed proteins. Other
applications using this technique include protein targets, site-specific tagging
of proteins, detection of DNA and RNA synthesis, detection of posttranslational
modifications in proteins, and visualization of glycan non-invasive imaging in a
Bio-Synthesis offers oligo synthesis and modifications for bioconjugation based
on bioorthogonal chemistry. These oligo bioorthogonal probes can be modified at
5’, 3’, or internally during chemical synthesis or conjugate post-synthetically.
We have provided hundreds of DNA or RNA conjugates using a variety of bioorthogonal
chemical reactions such as photoinduced cycloaddition of diaryl tetrazole to alkene,
1,3-dipolar cycloaddition between azides and cyclooctynes, also known as copper-free
click chemistry, strain promoted alkyne-azide cycloaddition (SPAAC), oxime/hydrazone
formation between aldehyde and ketones etc. Contact Bio-Synthesis for oligonucleotide
Bio-Synthesis offers a number of bioorthogonal reactions that can be use for detection,
tracking and imaging purposes. Our services include but not limited to: click chemistry,
Staudinger ligation, hydrazide-aldehyde reactions, aminoxy-aldehyde reactions and
Contact us to start your Bioorthogonal
Click chemistry is a reaction that uses cooper (I) as a catalyst and forms a 1,2,3-traizole
between an azide and alkyne modified oligonucleotide. See information about
Click Chemistry Modified Oligonucleotide.
Copper-free click chemistry is a bioorthogonal reaction developed as an activated
variant of an azide alkyne Huisgen cycloaddition. Cu-free click chemistry eliminates
a cytotoxic copper catalyst, allowing the reaction to proceed quickly and without
live cell toxicity. Although the reaction produces a regioisomeric mixture of triazoles,
the lack of regioselectivity in the reaction is not a major concern for its applications
in bioorthogonal chemistry. The bioorthogonal reaction has allowed the Cu-free click
reaction to be applied within cultured cells, live zebrafish, and mice.
Diel-alder reaction consists of a 4 + 2 cycloaddition between a diene and an alkene,
often called dienophile. Diene modified oligonucleotides can be prepared by solid-phase
synthesis using a 3,5-hexadiene phosphoramidite derivative, which could be incorporated
into the oligo at the 5' end.
The Trans-Cyclooctene-Tetrazine click chemistry is a very powerful tool in catalyst‐free
bioconjugation chemistry. The reaction follows an inverse‐electron demand Diels‐Alder
cycloaddition reaction of trans‐cyclooctenes (TCO) with tetrazines. This bioorthogonal
reaction possesses an exceptionally high reaction speed and nearly quantitative
yield under physiocological conditions with reaction rate constants 2000 M-1 s−1
(in 9:1 methanol/water). The extremely fast kinetics and selectivity enables the
conjugation of two low abundance biopolymers in an aqueous and otherwise complex
chemical environment through the formation of a stable dihydropyridazine. This bioorthogonal
reaction possesses extreme selectivity and biocompatibility, such that the complimentary
reagents can form covalent bonds within richly functionalized biological systems,
in some cases, living organisms.
The reaction between an aldehyde or ketone and a hydrazide or hydrazine functional
group to form a hydrzone bond has been frequently used for bioconjugation reaction.
Aldehyde, hydrazide modified oligonucleotides can be prepared by solid-phase synthesis
or functionalized post-synthetically.
The chemoselective conjugation of an aminooxy modified oligo with an aldehyde is
similar to that of the reaction of a hydrazide with an aldehyde, except instead
of giving a hydrazone bond it yields an oxime linkage. Aminooxy modified oligonucleotides
can be prepared by solid-phase synthesis using a 5'-aminooxy modifier 11. This modifier
is based on a tetraethylene glycol linkage for improved solubility and for reducing
the potential negative impact on hybridization of the oligo. The oxime formed from
the reaction of alkyloxyamines with aldehydes creates a stable covalent bond.