Poster abstracts

Poster number 30 submitted by Erwin Doe

Bioconjugation of functionalized oligodeoxynucleotides to hydrophobic fluorescence reporters

Erwin Doe (Ball State University), Hannah Hayth (Ball State University), Emil Khisamutdinov (Ball State University)

In the field of oligonucleotide (ODN) therapeutics, there is an imperative need to improve the ODNs properties by either chemical modification of the oligonucleotides structure or covalently linking reporter or therapeutic moieties with biologically relevant properties. The chemical conjugation can thus significantly improve the intrinsic property not only of ODNs but also reporter/therapeutic molecules. Bioconjugation of nucleic acids to small molecules also serve as nano-delivery facilities to transport drugs to specific targets. This study deployed azide–alkyne cycloaddition, a click reaction, to successfully conjugate a cyanine 3 alkyne moiety to an azide functionalized oligodeoxynucleotide 12-mer, as well as 3–azido–7–hydroxy–chromen–2–one, a coumarin azide to an alkyne functionalized ODN 27-mer. The application of Huisgen 1,3–dipolar cycloaddition of azides to terminal alkynes via a Cu(I)–catalyzed reaction pathway has been well established to produce high yield and stable 1,5–disubstituted 1,2,3–triazoles. Denaturing polyacrylamide gel electrophoresis confirmed the successful formation of the clicked products. Although cyanine 3 alkyne and coumarin azide are inherently fluorescent compounds, post-conjugation investigation of the clicked products demonstrated a drastic amplitude of fluorescent intensity by multiple fold. This amplification of fluorescence is attributable to the successful formation of the clicked ODNs which are characterized by the formation of the 1,2,3-triazole linkers.

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Keywords: Bioconjugation, Fluorescence, Oligodeoxynucleotide