Design and characterization of a novel pH-sensitive biocompatible and multifunctional nanocarrier for in vitro...

Breast cancer is one of the main reasons of women's mortality. A novel ternary combination of ZnAl-layered double hydroxides (LDH), cobalt ferrite (CoFe₂O₄) and N-graphene quantum dots (N-GQDs) proposes a pH-sensitive multifunctional nanocomposite that can improve therapeutic features of each compound; this is a notable strategy to make biocompatible materials with unique properties for paclitaxel (PTX) delivery in breast cancer cells. For proving the surface modification process of materials, electrochemical techniques including cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were carried out. By coating PEG on the surface of the N-GQDs/CoFe₂O₄/LDH, it developed a drug delivery system with low toxicity, an excellent encapsulation efficiency 88.4%, drug loading capacity of ca. 31%, and slow and sustained release behavior (9% after 72 h) under normal physiological conditions. Besides, a high drug release (~69%) at low-pH as a model of the extracellular tumor environment indicated a pH-sensitive release behavior. Moreover, cell viability assay proved the negligible cytotoxicity on normal cells (L929) and the improved growth inhibition effect of PTX/N-GQDs/CoFe₂O₄/LDH nanocarrier on MCF7 cancer cells. Blood compatibility test values with respect to red blood cell aggregation (RBC), coagulation prothrombin time (PT), activated partial thromboplastin time (APTT), and complement activation (C3 and C4 levels) remained within normal ranges without toxicity effect on RBCs and complement factors. Overall, this novel designed PTX/N-GQDs/CoFe₂O₄/LDH nanocarrier with tremendously biocompatible, slow-release and pH-dependent features could be considered as a theranostic candidate for various anticancer drugs delivery and cancer therapy.