The issue of water resource pollution resulting from the discharge of dyes is a matter of great concern for the environment. In this investigation, a new ternary heterogeneous Mg-Al LDH@g-C₃N₄X@Ag₃PO₄Y (X = wt % of g-C₃N₄ with respect to Mg-Al layered double hydroxide (LDH) and Y = wt % of Ag₃PO₄ loaded on Mg-Al LDH@g-C₃N₄30) nanocomposite was prepared with the aim of increasing charge carrier separation and enhancement of photocatalytic performance to degrade methylene blue (MB) dye. The prepared samples were subjected to characterization via Fourier-transform infrared spectroscopy, field emission scanning electron microscopy, energy-dispersive X-ray, transmission electron microscopy, X-ray diffraction, UV-vis diffuse reflectance spectroscopy, photoluminescence, and photoelectrochemical analysis. It was observed that in the presence of the composite of Mg-Al LDH and g-C₃N₄, the photocatalytic decomposition of MB under 150 W mercury lamp illumination increases significantly as opposed to Mg-Al LDH alone, and the Mg-Al LDH@g-C₃N₄ level with Ag₃PO₄ coating causes the complete degradation of MB to occur in less time. The outcomes show that the Mg-Al LDH@g-C₃N₄30@Ag₃PO₄5 nanocomposite demonstrated the highest photodegradation activity (99%). Scavenger tests showed that the two most effective agents in the photodegradation of MB are holes and hydroxyl radicals, respectively. Finally, a type II heterojunction photocatalytic degradation mechanism for MB by Mg-Al LDH@g-C₃N₄30@Ag₃PO₄5 was proposed.

In recent years, the role of optically sensitive nanomaterials has become powerful moieties in therapeutic techniques and has become particularly emphasized. Currently, by the extraordinary development of nanomaterials in different fields of medicine, they have found new applications. Phototherapy modalities, such as photothermal therapy (PTT) by toxic heat generation and photodynamic therapy (PDT) by reactive oxygen species, are known as promising phototherapeutic techniques, which can overcome the limitations of conventional protocols. Moreover, nanomaterial-based PDT and PTT match the simultaneous immune therapy and increase the immune system stimulation resulting from the denaturation of cancer cells. Nevertheless, nanomaterials should have sufficient biocompatibility and efficiency to meet PDT and PTT requirements as therapeutic agents. The present review focuses on the therapeutic potency of PDT, PTT, and also their combined modalities, which are known alternative protocols with minimal morbidity integrated into gold standard treatments such as surgery, chemotherapy, and radiation therapy at tumor treatment and cancer-related infectious diseases. In addition, for deeper understanding, photoablation effects with emphasis on the nature, morphology, and size of photosensitive nanomaterials in PDT and PTT were studied. Finally, transportation techniques and moieties needed as carriers of photosensitizers and photothermal therapy agents to hard-accessed regions, for example, cancerous regions, were investigated.

Introduction: In recent years, the use of cost-effective, multifunctional, environmentally friendly and simple prepared nanomaterials/nanoparticles have been emerged considerably. In this manner, different synthesizing methods were reported and optimized, but there is still lack of a comprehensive method with multifunctional properties. Materials and Methods: In this study, we aim to synthesis the copper oxide nanoparticles using Achillea millefolium leaf extracts for the first time. Catalytic activity was investigated by in situ azide alkyne cycloaddition click and also A³ coupling reaction, and optimized in terms of temperature, solvent, and time of the reaction. Furthermore, the photocatalytic activity of the synthesized nanoparticles was screened in terms of degradation methylene blue dye. Biological activity of the synthesized nanoparticles was evaluated in terms of antibacterial and anti-fungal assessments against Staphylococcus aureus, M. tuberculosis, E. coli, K. pneumoniae, P. mirabili, C. diphtheriae and S. pyogenes bacteria’s and G. albicans, A. flavus, M. canis and G. glabrata fungus. In the next step, the biosynthesized CuO-NPs were screened by MTT and NTU assays. Results: Based on our knowledge, this is a comprehensive study on the catalytic and biological activity of copper oxide nanoparticles synthesizing from Achillea millefolium, which presents great and significant results (in both catalytic and biological activities) based on a simple and green procedure. Conclusion: Comprehensive biomedical and catalytic investigation of the biosynthesized CuO-NPs showed the mentioned method leads to synthesis of more eco-friendly nanoparticles. The in vitro studies showed promising and considerable results, and due to the great stability of these nanoparticles in a green media, effective biological activity considered as an advantageous.

Quantum dots (QDs) with unique properties have been widely employed for energy, environmental, and health care applications. Green natural resources, because of their renewability, sustainability, abundance, low cost, and environmental-friendliness, can be utilized for the synthesis of diverse nanoarchitectures. This critical review highlights the recent advancements in the greener and sustainable synthesis of carbon, graphene and metal-based QDs, as well as their significant environmental applications such as photocatalytic hydrogen production, degradation of hazardous contaminants/pollutants and reduction of CO₂, with emphasis on the important challenges and future perspectives.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused the COVID-19 pandemic that has been spreading around the world since December 2019. More than 10 million affected cases and more than half a million deaths have been reported so far, while no vaccine is yet available as a treatment. Considering the global healthcare urgency, several techniques, including whole genome sequencing and computed tomography imaging have been employed for diagnosing infected people. Considerable efforts are also directed at detecting and preventing different modes of community transmission. Among them is the rapid detection of virus presence on different surfaces with which people may come in contact. Detection based on non-contact optical techniques is very helpful in managing the spread of the virus, and to aid in the disinfection of surfaces. Nanomaterial-based methods are proven suitable for rapid detection. Given the immense need for science led innovative solutions, this manuscript critically reviews recent literature to specifically illustrate nano-engineered effective and rapid solutions. In addition, all the different techniques are critically analyzed, compared, and contrasted to identify the most promising methods. Moreover, promising research ideas for high accuracy of detection in trace concentrations, via color change and light-sensitive nanostructures, to assist fingerprint techniques (to identify the virus at the contact surface of the gas and solid phase) are also presented.