DNA hairpin self-assembly on cell membrane triggered by Dual-aptamer logic circuit for cancer cell recognition and photodynamic therapy

Abstract

Integrated strategy of cancer diagnosis and therapy have found wide applications. The discovery of cancer biomarkers and corresponding aptamers makes it feasible for accurate identification of cancer cells and precise therapy. Herein, we report a dual aptamer based DNA logic circuit facilitating excellent signal amplification via hybridization chain reaction (HCR) for precise identification of cancer cells and photodynamic therapy. Aptamers Sgc4f and Sgc8c perform logic calculations with cell membrane biomarkers. HCR can only be triggered in the presence of both biomarkers to generate fluorescence amplification. A fluorophore (FAM) was modified at the 3′ end of hairpin H2 to indicate the logical calculation result, and G-quadruplex was extended at the 5′ end of H3 for loading the photosensitizer 5,10,15,20-tetrakis-(N-methyl-4-pyridyl) porphyrin (TMPyP4). Thanks to the intelligent autonomous computing capability of DNA logic circuit and signal amplification, the dual aptamer logic circuit enables accurate identification of target cancer cells and fluorescence imaging. TMPyP4-loaded hairpin endows the circuit with capability of targeting photodynamic therapy. Thus, the DNA logic circuit exhibits promising potential for accurate disease diagnosis and targeted therapy.