Preparation And Anti-cancer Activity Of Food Functional Factors/Two-dimensional Nanocomposites

As functional components that benefit for human health, food functional factors have been widely applied in our daily diet. In this dissertation, food functional factors and nanomaterials were combined to mutually supplement shortcomings of each other by absorbing each other’s merits, consequently improving performance of the both two elements. Hence, two two-dimensional nanocomposites were fabricated, namely astaxanthin/graphene oxide(GO-AST) and chitosan/molybdenum disulfide(CS-MoS2). The physicochemical properties and anticancer activities of two aforementioned nanocomposites were then investigated. In details, the results of the study are as following:(1) Preparation, physicochemical properties and anticancer activity of astaxanthin/graphene oxide 2D nanocompositeWith graphene oxide as host and astaxanthin as guest molecule, GO-AST 2D nanocomposites were prepared by a one-step mixing method. The as-prepared materials were then characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), UV visible spectrum and Fourier transform infrared spectrum(FT-IR). These results clearly confirmed the formation of GO–AST 2D nanocomposites. The mechanism of the interaction between GO and AST was attributed to the π-π stacking, hydrophobic and hydrogen-bond interactions. By the delivery of GO, the solubility of AST in water can be increased to 50.12 μg/mL. In addition, AST immobilized on GO shows higher light-thermal stability than that of native AST. Moreover, AST in GO–AST complex possesses potent antioxidant activity and cancer cell killing ability, which is stronger than that of native AST. Consequently, with the advantages of GO, the shortcomings of food functional factors, such as astaxanthin, can be significant improved.(2) Preparation and anticancer activity of chitosan/molybdenum disulfide 2D nanocompositeA one-step, large-scale and facile method, namely ionic liquid assisted grinding, was applied to obtain 2D molybdenum disulfide nanosheets with the functionalization of chitosan(CS-MoS2). The in vitro photothermal anticancer activity of CS-MoS2 2D nanocomposites was then investigated. The as-prepared materials were characterized by TEM, SEM, atomic force microscopy(AFM), FT-IR, UV-vis spectra, Raman spectroscopy and thermal gravimetric analysis(TGA). The results together proved the successful formation of CSMoS2 2D nanocomposites. Wherein, the content of chitosan in composite was calculated to be ca. 12.5 wt.%, and the yield of exfoliated MoS2 nanosheets was as high as 17%. The as-prepared CS-MoS2 possesses excellent storage stability, well biocompatibility and biostability. In addition, the as-prepared composite can efficiently kill cancer cells by hyperthermia induced by NIR irradiation. Consequently, chitosan can significantly improve the performance of MoS2 nanomaterials, which might accelerate their further development.