Computer-Customized Design of Graphene Oxide Logic Circuit Catalytic Hairpin Assembly Linkage (CHA-Linkage) Enables Molecular-Level Identification of Cancer Cells

Diagnosing cancer at the molecular level enables patients to receive life-saving treatments in a timely manner, but sensitivity, specificity, and high-throughput analyses of tumor markers are still great challenges. To address these issues, we developed an enzyme-free DNA logic circuit named CHA-Linkage, based on catalytic hairpin assembly (CHA) and graphene oxide (GO). Three different cancer cell microRNAs (miRNA) were chosen as "AND-OR" gate inputs, and three corresponding fluorescent signals were used as the outputs. Computer-customized design (CCD) allows customers to tailor CHA-Linkage circuit elements with regard to specific target combinations according to the identification needs of different cells, effectively avoiding sequence interference between circuit elements and providing an effective tool for high-throughput miRNA detection. Herein, GO is chosen as a carrier to deliver the CHA-Linkage circuit into cells as well as to quench the fluorescence. The developed CHA-Linkage features high sensitivity, high specificity, and high throughput. More importantly, the "open circuit" and "repair" within the CHA-Linkage system are simulated, allowing further differentiation of diverse cell types. This work enables precise identification of specific cancer cell types at the molecular level, offering a powerful tool for early cancer diagnosis and therapy.