Search Results (6)

Global pollution caused by micro/nanoplastics (M/NPs) is threatening agro-ecosystems, compromising food security and human health. Also, the increasing use of graphene-family nanomaterials (GFNs) in agricultural products has led to their widespread presence in agricultural systems. However, there is a large gap in the literature on the combined effects of MNPs and GFNs on agricultural plants. This study was conducted to explore the individual and combined impacts of polystyrene microplastics (PSMPs, 1 μm) or nanoplastics (PSNPs, 50–100 nm), along with agriculturally relevant graphene oxide (GO), on the seed germination and seedling growth of lettuce (Lactuca sativa). The results showed that the combined effects of mixtures of PSMPs/PSNPs and GO exhibited both synergism and antagonism, depending on different toxicity indicators. The cellular mechanism underlying the combined effects on the roots and shoots of seedlings involved oxidative stress. Three SOD family genes, namely, Cu/Zn-SOD, Fe-SOD, and Mn-SOD, played an important role in regulating the antioxidant defense system of seedlings. The extent of their contribution to this regulation was associated with both the distinct plastic particle sizes and the specific tissue locations within the seedlings. Full article

Numerous reports of graphene-family nanomaterials (GFNs) promoting plant growth have opened up a wide range of promising potential applications in agroforestry. However, several toxicity studies have raised growing concerns about the biosafety of GFNs. Although these studies have provided clues about the role of GFNs from different perspectives (such as plant physiology, biochemistry, cytology, and molecular biology), the mechanisms by which GFNs affect plant growth remain poorly understood. In particular, a systematic collection of data regarding differentially expressed genes in response to GFN treatment has not been conducted. We summarize here the fate and biological effects of GFNs in plants. We propose that soil environments may be conducive to the positive effects of GFNs but may be detrimental to the absorption of GFNs. Alterations in plant physiology, biochemistry, cytological structure, and gene expression in response to GFN treatment are discussed. Coincidentally, many changes from the morphological to biochemical scales, which are caused by GFNs treatment, such as affecting root growth, disrupting cell membrane structure, and altering antioxidant systems and hormone concentrations, can all be mapped to gene expression level. This review provides a comprehensive understanding of the effects of GFNs on plant growth to promote their safe and efficient use. Full article

Based on statistics from the National Cancer Institute in the US, the rate of new cases of cancer is 442.4 per 100,000 men and women per year, and more than one-third do not survive the disease. Cancer diagnosis and treatment are the most important challenges in modern medicine. The majority of cancer cases are diagnosed at an early stage. However, the possibility of simultaneous diagnosis and application of therapy (theranostics) will allow for acceleration and effectiveness of treatment. Conventional chemotherapy is not effective in reducing the chemoresistance and progression of various types of cancer. In addition, it causes side effects, which are mainly a result of incorrect drug distribution. Hence, new therapies are being explored as well as new drug delivery strategies. In this regard, nanotechnology has shown promise in the targeted delivery of therapeutics to cancer cells. This review looks at the latest advances in drug delivery-based diagnosis and therapy. Drug delivery nanosystems made of various types of carbon (graphene, fullerenes, and carbon nanotubes) are discussed. Their chemical properties, advantages, and disadvantages are explored, and these systems are compared with each other. Full article

Given the industrial revolutions and resource scarcity, the development of green technologies which aims to conserve resources and reduce the negative impacts of technology on the environment has become a critical issue of concern. One example is heterogeneous photocatalytic degradation. Titanium dioxide (TiO₂) has been intensively researched given its low toxicity and photocatalytic effects under ultraviolet (UV) light irradiation. The advantages conferred by the physical and electrochemical properties of graphene family nanomaterials (GFN) have contributed to the combination of GFN and TiO₂ as well as the current variety of GFN-TiO₂ catalysts that have exhibited improved characteristics such as greater electron transfer and narrower bandgaps for more potential applications, including those under visible light irradiation. In this review, points of view on the intrinsic properties of TiO₂, GFNs (pristine graphene, graphene oxide (GO), reduced GO, and graphene quantum dots (GQDs)), and GFN-TiO₂ are presented. This review also explains practical synthesis techniques along with perspective characteristics of these TiO₂- and/or graphene-based materials. The enhancement of the photocatalytic activity by using GFN-TiO₂ and its improved photocatalytic reactions for the treatment of organic, inorganic, and biological pollutants in water and air phases are reported. It is expected that this review can provide insights into the key to optimizing the photocatalytic activity of GFN-TiO₂ and possible directions for future development in these fields. Full article

Graphene family nanomaterials (GFNs), including graphene, graphene oxide (GO), reduced graphene oxide (rGO), and graphene quantum dots (GQDs), have manifold potential applications, leading to the possibility of their release into environments and the exposure to humans and other organisms. However, the genotoxicity of GFNs on DNA remains largely unknown. In this review, we highlight the interactions between DNA and GFNs and summarize the mechanisms of genotoxicity induced by GFNs. Generally, the genotoxicity can be sub-classified into direct genotoxicity and indirect genotoxicity. The direct genotoxicity (e.g., direct physical nucleus and DNA damage) and indirect genotoxicity mechanisms (e.g., physical destruction, oxidative stress, epigenetic toxicity, and DNA replication) of GFNs were summarized in the manuscript, respectively. Moreover, the influences factors, such as physicochemical properties, exposure dose, and time, on the genotoxicity of GFNs are also briefly discussed. Given the important role of genotoxicity in GFNs exposure risk assessment, future research should be conducted on the following: (1) developing reliable testing methods; (2) elucidating the response mechanisms associated with genotoxicity in depth; and (3) enriching the evaluation database regarding the type of GFNs, applied dosages, and exposure times. Full article

Together with the enhancement of the load-bearing implant process for bone substitution and reproduction, an increasing requirement was observed concerning biodegradable magnesium and its alloys with lighter density and outstanding characteristics. Regardless of the current great potential of Mg utilization currently, the broader use of Mg alloys continues to be constrained by several natural causes, such as low resistance of corrosion, inadequate mechanical integrity during the healing process, and poor antibacterial performance. In this perspective, Mg-based composite encapsulated within graphene family nanomaterials (GFNs) such as graphene (Gr), graphene oxide (GO), graphene nanoplatelets (GNPs), and reduced graphene oxide (rGO) as reinforcement agents present great antibacterial activity, as well as cellular response and depicted numerous benefits for biomedical use. Magnesium matrix nanocomposites reinforced with GFNs possess enhanced mechanical properties and high corrosion resistance (low concentration graphene). It is worth noting that numerous elements including the production technique of the Mg-based composite containing GFNs and the size, distribution, and amounts of GFNs in the Mg-based matrix have a crucial role in their properties and applications. Then, the antibacterial mechanisms of GFN-based composite are briefly described. Subsequently, the antibacterial and strengthening mechanisms of GFN-embedded Mg-based composites are briefly described. This review article is designed to wrap up and explore the most pertinent research performed in the direction of Mg-based composites encapsulated within GFNs. Feasible upcoming investigation directions in the field of GFN-embedded Mg-based composites are discussed in detail. Full article