Abstract: Objective: To develop IFN-γ DNA aptamer that may potentially serve as a binding ligand in novel aptamer-based IFN-γ detection. Methods: A single-stranded 59nt DNA library containing 21 random oligonucleotides was synthesized in vitro. A new aptamer B3-8 was developed by SELEX technique with IFN-γ protein as target. Flow cytometry was performed to monitor the enrichment of aptamer pool and to evaluate the binding properties of B3-8. The structure of B3-8 was predicted by MFold software. Results: The aptamer B3-8 bound to the IFN-γ with a Kd of nmol/L, and had minimal cross reactivity with BSA. Conclusions: B3-8 may have application potentials in IFN-γ assay.

Key words: aptamer, SELEX, IFN-γ