Folic Acid-decorated and PEGylated Graphene Quantum Dots as efficient Tamoxifen delivery system against breast cancer cells: in vitro studies

Nano-drug delivery systems have provided a platform for improving the formulations of targeted cancer therapy. Graphene quantum dots (GQDs) possess potential properties for the targeted transport and tracking of anticancer medication to tumor cells. For this purpose, the synthesized GQDs were decorated with folic acid for better binding to folate-positive breast cancer cells and methoxy polyethylene glycol (mPEG2000) for a longer lifetime, and finally loaded with anticancer drug tamoxifen (TMX). The synthesized nano-drugs were characterized using FTIR, XRD, UV-vis, PL, HRTEM, FESEM, and DLS analytical devices. Based on the obtained data, the average hydrodynamic diameter of particles dissolved in water was 294.7 nm and the size of dehydrated particles was between 3 and 153 nm. PL data showed that prepared nanoparticles have an emission wavelength of 438 nm, which is in the blue fluorescent wavelength range, thus making these nanoparticles suitable for cell imaging. The encapsulation efficiency and loading percentage of tamoxifen in nanoparticles were calculated at about 52.5% and 30%, respectively, and cumulative drug release reached 89% within 42 hours. The cytotoxicity effects of nanoparticles on MCF-7 cell line were investigated. The targeted mPEG-GQDs-FA/TMX (TMX-FPGs) nano-drug was more toxic than free TMX drug on MCF-7 cells and had reduced side effects on healthy HDF cells. TMX-FPGs induced apoptosis cell death in cancer cells, significantly. The confocal cell imaging experiments showed that TMX-FPGs are appropriate for monitoring and targeting MCF-7 cancer cells. These data have approved the potency of TMX-FPGs against breast cancer cells.