DNA-based nanocomposites with secondary structure for precision treatment of tumor

Carbon dots (CDs) have been extensively studied in tumor therapy due to their excellent compatibility, remarkable stability, and luminescent properties. However, CDs-based therapeutic agents often face limitations such as rapid clearance, poor targeting, and weak responsiveness, which hinder their efficacy in achieving precise tumor treatment. To address these challenges, this study presents the construction of a dual-targeting, dual-responsive drug delivery platform with hierarchical structures: MV-DNA-CDs@DOX. Firstly, methacrylic acid-coated o-phenylenediamine carbon dots were synthesized using methacrylic acid and o-phenylenediamine. This was then conjugated with an i-motif-containing DNA sequence to create DNA-CDs with a "yarn ball-like" secondary structure. The nano-particles preserved the acid-responsive nature of the sequence and introduced an additional photo-responsive characteristic, enhancing the nanocarrier's ability to deliver drugs deeply into tumor tissues. Upon loading with DOX, the polymeric nanocarrier was subject to biomimetic treatment, endowing it with active tumor-targeting capabilities and improving the specific distribution of the drug within tumor sites. Therefore, the use of biocompatible and responsive DNA segments as crosslinkers to construct organic nanopolymer carriers in the preparation of anti-tumor nanomaterials holds promise in expanding the application of nanotechnology in the field of cancer treatment.