Development of advanced drug-loaded graphene quantum dots with improved photoluminescence properties for enhanced...

In this study, a new system of drug-functionalized graphene quantum dots (GQDs) is presented for combined therapeutic delivery and imaging. To do this, doxorubicin (DOX), which is a strong anticancer reagent, is chosen due to its organic nature. Additionally, to investigate quantum confinement effects on the system's efficiency, diamond-shaped GQDs with two different sizes are utilized. We theoretically investigate the optoelectronic and photoluminescence behavior of various drug-GQD arrangements, to evaluate their nanomedical diagnostic efficiency. The findings confirm the accuracy of the systems investigated. The stability of the hybrid structures is confirmed by the absence of imaginary frequencies. As the size of GQD increases, the HOMO-LUMO gap energy decreases under the regulation of drug binding and nanoparticles hardness. This size-dependent effect also causes a red-shift in the optical emission and absorption spectra upon DOX conjugation. Furthermore, DOX-conjugated GQDs exhibit strong near-infrared photoluminescence, suggesting their application potential in drug delivery and diagnostics in nanomedicine.