Metabolomics approach to study in vivo toxicity of graphene oxide nanosheets

Hazard assessment of hexagonal boron nitride and hexagonal boron nitride reinforced thermoplastic polyurethane composites using human skin and lung cells

Hexagonal boron nitride (hBN) is an emerging two-dimensional material attracting considerable attention in the industrial sector given its innovative physicochemical properties. Potential risks are associated mainly with occupational exposure where inhalation and skin contact are the most relevant exposure routes for workers. Here we aimed at characterizing the effects induced by composites of thermoplastic polyurethane (TPU) and hBN, using immortalized HaCaT skin keratinocytes and BEAS-2B bronchial epithelial cells. The composite was abraded using a Taber® rotary abraser and abraded TPU and TPU-hBN were also subjected to photo-Fenton-mediated degradation mimicking potential weathering across the product life cycle. Cells were exposed to the materials for 24 h (acute exposure) or twice per week for 4 weeks (chronic exposure) and evaluated with respect to material internalization, cytotoxicity, and proinflammatory cytokine secretion. Additionally, comprehensive mass spectrometry-based proteomics and metabolomics (secretomics) analyses were performed. Overall, despite evidence of cellular uptake of the material, no significant cellular and/or protein expression profiles alterations were observed after acute or chronic exposure of HaCaT or BEAS-2B cells, identifying only few pro-inflammatory proteins. Similar results were obtained for the degraded materials. These results support the determination of hazard profiles associated with cutaneous and pulmonary hBN-reinforced polymer composites exposure.

In vivo safety evaluation method for nanomaterials for cancer therapy

Nanomaterials are extensively used in the diagnosis and treatment of cancer and other diseases because of their distinctive physicochemical properties, including the small size and ease of modification. The approval of numerous nanomaterials for clinical treatment has led to a significant increase in human exposure to these materials. When nanomaterials enter organisms, they interact with DNA, cells, tissues, and organs, potentially causing various adverse effects, such as genotoxicity, reproductive toxicity, immunotoxicity, and damage to tissues and organs. Therefore, it is crucial to elucidate the side effects and toxicity mechanisms of nanomaterials thoroughly before their clinical applications. Although methods for in vitro safety evaluation of nanomaterials are well established, systematic methods for in vivo safety evaluation are still lacking. This review focuses on the in vivo safety evaluation of nanomaterials and explores their potential effects. In addition, the experimental methods for assessing such effects in various disciplines, including toxicology, pharmacology, physiopathology, immunology, and bioinformatics are also discussed.

Better biocompatibility of nitrogen-doped graphene compared with graphene oxide by reducing cell autophagic flux blockage and cell apoptosis

Nitrogen-doped graphene (C2 N), a novel graphene-based materials, has been proposed as a potential alternative to graphene oxide (GO) in biomedical applications. However, due to the challenges in synthesizing C2 N, reports in the biomedical field are currently rare. Here, we have modified the reported procedure and successfully synthesized C2 N nanoparticles at 120°C, which we refer to as C2 N-120. The toxicity and biocompatibility of GO and C2 N-120 were evaluated using a mouse model injected with GO/C2 N-120 via the tail vein, as well as cell models treated with GO/C2 N-120. In vivo studies revealed that GO/C2 N-120 showed similar distribution patterns after tail vein injection. The liver, spleen, and lung are the major nanoparticle uptake organs of GO and C2 N-120. However, GO deposition in the major nanoparticle uptake organs was more significant than that of C2 N-120. In addition, GO deposition caused structural abnormalities, increased apoptotic cells, and enhanced macrophage infiltration whereas C2 N-120 exhibited fewer adverse effects. In vitro experiments were conducted using different cell lines treated with GO/C2 N-120. Unlike GO which induced mitochondrial damage, oxidative stress, inflammatory response, autophagic flux blockage and cell apoptosis, C2 N-120 showed lower cytotoxicity in cell models. Our data demonstrated that C2 N-120 exhibits higher biocompatibility than GO, both in vivo and in vitro, suggesting its potential for biomedical application in the future.

Carbon Nanotubes and Graphene Materials as Xenobiotics in Living Systems: Is There a Consensus on Their Safety?

Carbon nanotubes and graphene are two types of nanomaterials that have unique properties and potential applications in various fields, including biomedicine, energy storage, and gas sensing. However, there is still a debate about the safety of these materials, and there is yet to be a complete consensus on their potential risks to human health and the environment. While some studies have provided recommendations for occupational exposure limits, more research is needed to fully understand the potential risks of these materials to human health and the environment. In this review, we will try to summarize the advantages and disadvantages of using carbon nanotubes and graphene as well as composites containing them in the context of their biocompatibility and toxicity to living systems. In addition, we overview current policy guidelines and technical regulations regarding the safety of carbon-based nanomaterials.

Synthesis and Functionalization of Graphene Materials for Biomedical Applications: Recent Advances, Challenges, and Perspectives

Since its discovery in 2004, graphene is increasingly applied in various fields owing to its unique properties. Graphene application in the biomedical domain is promising and intriguing as an emerging 2D material with a high surface area, good mechanical properties, and unrivalled electronic and physical properties. This review summarizes six typical synthesis methods to fabricate pristine graphene (p-G), graphene oxide (GO), and reduced graphene oxide (rGO), followed by characterization techniques to examine the obtained graphene materials. As bare graphene is generally undesirable in vivo and in vitro, functionalization methods to reduce toxicity, increase biocompatibility, and provide more functionalities are demonstrated. Subsequently, in vivo and in vitro behaviors of various bare and functionalized graphene materials are discussed to evaluate the functionalization effects. Reasonable control of dose (<20 mg kg^-1 ), sizes (50-1000 nm), and functionalization methods for in vivo application are advantageous. Then, the key biomedical applications based on graphene materials are discussed, coupled with the current challenges and outlooks of this growing field. In a broader sense, this review provides a comprehensive discussion on the synthesis, characterization, functionalization, evaluation, and application of p-G, GO, and rGO in the biomedical field, highlighting their recent advances and potential.

Trends and prospects in graphene and its derivatives toxicity research: A bibliometric analysis

The purpose of this paper is to explore the current research status, hot topics, and future prospects in the field of graphene and its derivatives toxicity. In the article, the Web of Science Core Collection database was used as the data source, and the CiteSpace and VOSviewer were used to conduct a visual analysis of the last 10 years of research on graphene and its derivatives toxicity. A total of 8573 articles were included, and we analyzed the literature characteristics of the research results in the field of graphene and its derivatives toxicity, as well as the distribution of authors and co-cited authors; the distribution of countries and institutions; the situation of co-cited references; and the distribution of journals and categories. The most prolific countries, institutions, journals, and authors are China, the Chinese Academy of Sciences, RSC Advances, and Wang, Dayong, respectively. The co-cited author with the most citations was Akhavan, Omid. The five research hotspot keywords in the field of graphene and its derivatives toxicity were "nanomaterials," "exposure," "biocompatibility," "adsorption," and "detection." Frontier topics were "facile synthesis," "antibacterial activity," and "carbon dots." Our study provides perspectives for the study of graphene and its derivatives toxicity and yields valuable information and suggestions for the development of graphene and its derivatives toxicity research in the future.

Age- and Lifespan-Dependent Differences in GO Caused DNA Damage in Acheta domesticus

The rising applicability of graphene oxide (GO) should be preceded by detailed tests confirming its safety and lack of toxicity. Sensitivity to GO of immature, or with different survival strategy, individuals has not been studied so far. Therefore, in the present research, we focused on the GO genotoxic effects, examining selected parameters of DNA damage (total DNA damage, double-strand breaks-DSB, 8-hydroxy-2'-deoxyguanosine-8-OHdG, abasic site-AP sites), DNA damage response parameters, and global methylation in the model organism Acheta domesticus. Special attention was paid to various life stages and lifespans, using wild (H), and selected for longevity (D) strains. DNA damage was significantly affected by stage and/or strain and GO exposure. Larvae and young imago were generally more sensitive than adults, revealing more severe DNA damage. Especially in the earlier life stages, the D strain reacted more intensely/inversely than the H strain. In contrast, DNA damage response parameters were not significantly related to stage and/or strain and GO exposure. Stage-dependent DNA damage, especially DSB and 8-OHdG, with the simultaneous lack or subtle activation of DNA damage response parameters, may result from the general life strategy of insects. Predominantly fast-living and fast-breeding organisms can minimize energy-demanding repair mechanisms.