L-RNA aptamer cyclization and use thereof

Patent metadata

Field	Value
Publication number	US-12410432-B2
Application number	US-202117236600-A
Country	US
Kind code	B2
Filing date	Apr 21, 2021
Priority date	Apr 21, 2021
Publication date	Sep 9, 2025
Grant date	Sep 9, 2025

Abstract

A method of cyclizing an L-RNA aptamer by modifying the aptamer with a 3′ azide and a 5′ alkyne group and using click chemistry reaction-based method. The cyclized L-RNA aptamers have improved binding properties and favour more in vitro/cell applications. Also disclosed is an L-oligonucleotide aptamer having linked ends.

First claim

What is claimed is:

1. A method of linking two terminal ends of oligonucleotide, wherein one of the terminal oligonucleotide ends has a 5′ terminal alkyne; and the other one of the terminal oligonucleotide ends has a 3′ azide residue; comprising the step of:
linking the 5′ terminal alkyne to the 3′ azide residue,
wherein the oligonucleotide is L-Apt.4-1c comprising the nucleotide sequence of SEQ ID NO: 1.

2. A method of joining two terminal ends of an oligonucleotide as claimed in claim 1 , wherein the step of linking the 5′ terminal alkyne to the 3′ azide residue is carried out in the presence of a catalyst for azide-alkyne cycloaddition.

3. A method of joining two terminal ends of an oligonucleotide as claimed in claim 2 , wherein the catalyst is Cu(I).

4. A method of joining two terminal ends of an oligonucleotide as claimed in claim 3 , wherein the step of providing a catalyst for azide-alkyne cycloaddition comprises:
providing Cu in a higher oxidation state; and
a reducing agent to reduce the Cu in a higher oxidation state to Cu(I).

5. A method of joining two terminal ends of an oligonucleotide as claimed in claim 4 , wherein the Cu is provided in the form of copper (II) complex with the ligand tris(benzyltriazolylmethyl)amine.

6. A method of joining two terminal ends of an oligonucleotide as claimed in claim 4 , wherein the reducing agent is ascorbic acid or its salt.

7. A method of joining two terminal ends of an oligonucleotide as claimed in claim 4 , wherein the Cu in a higher oxidation state is Cu(II)-TBTA.

Assignees

• Univ City
• Univ City Hong Kong

Inventors

• Kwok Chun Kit
• Ji Danyang

Classifications

• C12N2310/16

  Aptamers · CPC title

• C07F9/6587

  having two phosphorus atoms as ring hetero atoms in the same ring · CPC title

• C07F9/572

  Five-membered rings · CPC title

• C12N2310/532

  Closed or circular · CPC title

• C12N15/115 Primary

  Aptamers, i.e. nucleic acids binding a target molecule specifically and with high affinity without hybridising therewith {; Nucleic acids binding to non-nucleic acids, e.g. aptamers} · CPC title