The proposed project will develop a novel diagnostic reagent that detects cancer-associated cell surface proteins. Specifically, a bioactive peptide that can bind to the cell surface proteins will be displayed on the synthetic chromatin and examined its selective binding affinity to cancer cells. To this end, plasmid DNA and recombinant proteins will be purified from E. coli and the synthetic chromatin will be assembled by a self-assembly process. The synthetic chromatin will be validated by cell-based binding assays for measuring the binding affinity. The project will explore the possibility of synthetic chromatin as an effective cancer diagnostic tool and cancer immunotherapy.