▎ 摘　　要

Cancer is one of the most serious global threats to human health, which arises as a result of the uncontrolled proliferation of malignant cells. In this regard, several traditional cancer treatment strategies are available, but these treatments are associated with several adverse side effects which are responsible for the high mortality rate of cancer patients. Therefore, the development of novel and efficient drug delivery vehicles for localized and targeted delivery of existing chemotherapeutics are urgently needed. In this work, multi-functionalized graphene oxide based novel drug nanocarrier was developed for the effective delivery of chemotherapeutics, viz. quercetin (QUE) and curcumin (CUR). For this, the surface of graphene oxide (GO) was first modified with branched polyethylenimine (BPEI), a cationic hydrophilic polymer. Then, the surface of GO-BPEI was grafted with metal oxides, namely zinc oxide (ZnO) and titanium dioxide (TiO2) via a simple co-precipitation method. The anti-cancer drugs QUE and CUR were separately loaded onto multi-functionalized graphene oxide (GO-BPEI-ZT) via non-covalent interactions. QUE and CUR loading capacity (LC%) of GO-BPEI-ZT were found to be 49.39% (QUE) and 48.89% (CUR) respectively. The release behavior of drugs loaded nanocarriers was also studied and we found that the synthesized nanocarrier exhibits a pH-sensitive release of loaded drugs. Finally, the cytotoxicity of developed nanocarrier systems was examined against MDA MB 231 cell line (human breast cancer cell line). The results demonstrate that the drugs-loaded nanocarriers exhibit remarkable cytotoxicity towards breast cancer cells compared to the respected pure drugs. The purpose of this investigation is to develop a promising drug nanocarrier for effective and site-specific drug delivery as well as to improve the anticancer efficacy of existing chemotherapeutics.