Copper sulfide nanostructures: synthesis and biological applications.

Over the past few years, considerable attention has been paid to biomedical applications of copper sulfide nanostructures owing to their enhanced physiochemical and pharmacokinetics characteristics in comparison to gold, silver, and carbon nanomaterials. The small-sized Cu x S y nanoparticles have the advantage to absorb efficiently in the near-infrared region (NIR) above 700 nm and the absorption can be tuned by altering their stoichiometries. Moreover, their easy removal through the kidneys overpowers the issue of toxicity caused by many inorganic substances. The low cost and selectivity further add to the advantages of Cu x S y nanostructures as electrode materials in comparison to relatively expensive materials such as silver and gold nanoparticles. This review is mainly focused on the synthesis and biomedical applications of Cu x S y nanostructures. The first part summarizes the various synthetic routes used to produce Cu x S y nanostructures with varying morphologies, while the second part targets the recent progress made in the application of small-sized Cu x S y nanostructures as biosensors, and their analysis and uses in the cure of cancer. Photoacoustic imaging and other cancer treatment applications are discussed. Research on Cu x S y nanostructures will continue to increase over the next few decades, and great opportunities lie ahead for potential biomedical applications of Cu x S y nanostructures.

Photocatalytic Z-Scheme Overall Water Splitting: Recent Advances in Theory and Experiments.

Photocatalytic water splitting is considered one of the most important and appealing approaches for the production of green H2 to address the global energy demand. The utmost possible form of artificial photosynthesis is a two-step photoexcitation known as "Z-scheme", which mimics the natural photosystem. This process solely relies on the effective coupling and suitable band positions of semiconductors (SCs) and redox mediators for the purpose to catalyze the surface chemical reactions and significantly deter the backward reaction. In recent years, the Z-scheme strategies and their key role have been studied progressively through experimental approaches. In addition, theoretical studies based on density functional theory have provided detailed insight into the mechanistic aspects of some breathtakingly complex problems associated with hydrogen evolution reaction and oxygen evolution reaction. In this context, this critical review gives an overview of the fundamentals of Z-scheme photocatalysis, including both theoretical and experimental advancements in the field of photocatalytic water splitting, and suggests future perspectives.

Phytofabrication of cobalt oxide nanoparticles from Rhamnus virgata leaves extract and investigation of different bioactivities.

The tunable cobalt oxide nanoparticles (CoONPs) are produced due to the phytochemicals present in Rhamnus virgata (RhV) leaf extract which functions as reducing and stabilization agents. The synthesis of CoONPs was confirmed using different analytical techniques: UV-Vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), dynamics light scatterings (DLS), Fourier-transform infrared spectroscopy (FTIR), energy dispersive X-ray, and Raman spectroscopy analyses. Furthermore, multiple biological activities were performed. Significant antifungal and antibacterial potentials have been reported. The in vitro cytotoxic assays of CoONPs revealed strong anticancer activity against human hepatoma HUH-7 (IC50 : 33.25 µg/ml) and hepatocellular carcinoma HepG2 (IC50 : 11.62 µg/ml) cancer cells. Dose-dependent cytotoxicity potency was confirmed against Leishmania tropica (KMH23 ); amastigotes (IC50 : 58.63 µg/ml) and promastigotes (IC50 : 32.64 µg/ml). The biocompatibility assay using red blood cells (RBCs; IC50 : 4,636 µg/ml) has confirmed the bio-safe nature of CoONPs. On the whole, results revealed nontoxic nature of RhV-CoONPs with promising biological potentials.