ZnO-ZnS Heterostructure as a Potent Photocatalyst in the Preparation of Some Substituted Chromenes and Remarkable Antigastrointestinal Cancer Activity

Abstract

The nanosized hybrid material ZnO-ZnS was synthesized using the well-known sol−gel method, as a simple and environmentally friendly procedure. The material was then characterized using various techniques including FESEM, TEM, UV−vis, DRS, EDS, XRD, and FT-IR. The characterization studies revealed the generation of ZnO-ZnS nanoparticles with a mean size of around 25 nm. Moreover, DRS analysis provided a band gap of 3.05 eV for this nanomaterial. The photocatalytic properties of the ZnO-ZnS heterojunction was investigated in the synthesis of some substituted chromenes under mild reaction conditions. The results showed that the prepared nanophotocatalyst exhibits significantly higher activity compared to its individual components (ZnO and ZnS) and provides 73−87% yield with 0.01 g of ZnO-ZnS after 30 min. In addition, the nanophotocatalyst demonstrated a high reusability in the desired condensation reaction. The enhanced photocatalytic activity of ZnO-ZnS can be attributed to the slower recombination of the electron−hole pairs in this semiconductor material. The reactive species OH • , • O 2 − , and h + are believed to play important roles in the photocatalytic system. Furthermore, cellular toxicity of ZnO-ZnS nanoparticles was evaluated on HCT-116 human gastrointestinal cancer cell line by MTT assay. The results proved a distinct reduction of cell viability, proofing cytotoxicity of nanoparticles on the cancer cells. This study highlights the potential of the nanoparticles against gastrointestinal cancer.

Zinc oxide‐cadmium(II) sulfide heterostructure as a potential photocatalyst for preparing substituted chromenes and its anti‐liver cancer activity

“…By comparing the viability of cancer cells and normal cells after nanoparticle treatment, then, the selectivity of nanoparticles in inducing cytotoxic effects can be assessed. Up to now, various simple or decorated metal oxide nanoparticles as well as many plant extracts have been documented because of their anticancer and cytotoxic properties 27–40 . One mechanism by which metal oxide nanoparticles induce cytotoxic effects is through the generation of reactive oxygen species (ROS) that induce oxidative stress and damage.…”

“…Up to now, various simple or decorated metal oxide nanoparticles as well as many plant extracts have been documented because of their anticancer and cytotoxic properties. [27][28][29][30][31][32][33][34][35][36][37][38][39][40] One mechanism by which metal oxide nanoparticles induce cytotoxic effects is through the generation of reactive oxygen species (ROS) that induce oxidative stress and damage. Because cancer cells are frequently associated with higher levels of ROS, they may be more susceptible to the additional oxidative damage.…”