Conventional methods for attaching single-stranded DNA (ssDNA) to IgG antibodies often face several challenges. These include high costs associated with ssDNA modification, low coupling efficiency, complex reaction and purification processes, and difficulties in controlling the stoichiometry between ssDNA and IgG. 

Professor Hang Xing from Hunan University developed the "AND Linker”, a bifunctional fusion protein that enables facile and efficient crosslinking of diverse IgG with ssDNA. The “AND Linker” includes two functional domains. 

• A specific single-stranded DNA (ssDNA) binding domain that can covalently bind to the sequence 5'-AAGTATTACCAGAAA-Target Sequence-3' (with the underscore marking the cleavage and binding site). After cleavage, the Linker covalently binds with the 5'-phosphate and generates the “AND Linker -5'-ACCAGAAA-Target Sequence-3'”.
• A specific antibody Fc end binding domain that can stably couple with the Fc domain of IgG with binding affinity around 20 nM – 0.2 nM, ultimately forming stable IgG-ssDNA conjugates with a stoichiometric ratio of 1:1 (See Figure).

Advantages of AND Linker

• Precisely controlled Antibody-DNA conjugate with a stoichiometry ratio of 1:1;
• Overall reaction time < 1 hour;
• Specific connection with the antibody Fc domain;
• Applicable to diverse native IgG of different species;
• No need to modify ssDNA .

Applications 

The AND Linker can be used in Immuno-PCR (Immuno-Polymerase Chain Reaction), Proximity Ligation Assay (PLA), Proximity Extension Assay (PEA), and other cellular analysis applications. 

Reference

Chemical Biology Approaches Toward Precise Structure Control of IgG-based Antibody-Oligonucleotide Conjugates
Lin Shen, Yuanyuan Wu, Wenxue Xie, Guangyao Chen, and Hang Xing

Product

Cat# 984538 AND linker(Antibody-DNA linker), 90%

Biography

Hang Xing is a Professor of Chemistry at Hunan University. He received his B.S. and M.S. degree from Nanjing University with Prof. Junfeng Bai, and Ph.D. degree from UIUC in 2014 with Prof. Yi Lu. He then moved to Northwestern University working with Prof. Chad A. Mirkin as a postdoctoral research fellow before joining Hunan University in 2017. His research focuses on developing cellular interface chemistries with spatiotemporal control and precise DNA-protein conjugation approaches.