Design of a Nanodelivery System with High Loading Efficiency by Improving π-π Interactions with Drugs

Graphical Herein, we constructed a novel carbon nitride compound called PTCNx, featuring a large π-conjugated skeleton, and employed it as a carrier for delivering aromatic clinical drugs for the first time. PTCN 550 achieving an unprecedented 99 % loading efficacy of DOX and resulting PTCN 550 -DOX demonstrated effective anti-tumor activity for CNE-2Z tumor cells. π-π interactions, serving as a pivotal driving force, hold enduring significance in the realm of drug delivery system development, primarily due to the prevalence of aromatic moieties in a substantial number of clinically relevant pharmaceutical compounds. Herein, we constructed a novel carbon nitride compound called PTCNx, featuring a large π-conjugated skeleton, and employed it as a carrier for delivering aromatic clinical drugs for the first time. We conducted sequence characterization of their chemical structure, optical properties, and morphology, along with extensive research to analyze their significant enhancement in drug loading capacity. Of particular note was the exceptional loading efficiency of Doxorubicin (DOX) under alkaline conditions, achieving an unexpected 99 % efficacy, significantly surpassing the capabilities of traditional carbon nitrides with limited π-conjugated systems. Cell tests illustrated that PTCN 550 carrier exhibited favorable biocompatibility and low toxicity for normal and tumor cells, showing its potential as a drug carrier. However, PTCN 550 -DOX complex effectively inhibited both A549 and CNE-2Z tumor cells. And it demonstrated more effective anti-tumor activity for CNE-2Z than for A549 cells. This study marks a significant milestone, representing the inaugural endeavor to elucidate the improvement in loading capacity through the strategic extension of the π-conjugated system design paradigm.