Size- and Oxidation-Dependent Toxicity of Graphene Oxide Nanomaterials in Embryonic Zebrafish

Ecotoxicity and environmental safety assessment of two-dimensional niobium carbides (MXenes)

Two-dimensional (2D) MXenes have gained great interest in water treatment, biomedical, and environmental applications. The antimicrobial activity and cell toxicity of several MXenes including Nb4C3Tx and Nb2CTx have already been explored. However, potential side effects related to Nb-MXene toxicity, especially on aquatic pneuma, have rarely been studied. Using zebrafish embryos, we investigated and compared the potential acute toxicity between two forms of Nb-MXene: the multilayer (ML-Nb4C3Tx, ML-Nb2CTx) and the delaminated (DL-Nb2CTx, and DL-Nb4C3Tx) Nb-MXene. The LC50 of ML-Nb4C3Tx, ML-Nb2CTx, DL-Nb2CTx, and DL-Nb4C3Tx were estimated to be 220, 215, 225, and 128 mg/L, respectively. Although DL-Nb2CTx, and DL-Nb4C3Tx derivatives have similar sizes, DL-Nb4C3Tx not only shows the higher mortality (LC50 = 128 mg/L Vs 225 mg/L), but also the highest teratogenic effect (NOEC = 100 mg/L Vs 200 mg/L). LDH release assay suggested more cell membrane damage and a higher superoxide anion production in DL-Nb4C3Tx than DL-Nb2CTx,. Interestingly, both DL-Nb-MXene nanosheets showed insignificant cardiac, hepatic, or behavioral toxic effects compared to the negative control. Embryos treated with the NOEC of DL-Nb2CTx presented hyperlocomotion, while embryos treated with the NOEC of DL-Nb4C3Tx presented hyperlocomotion, suggesting developmental neurotoxic effect and muscle impairment induced by both DL-Nb-MXene. According to the Fish and Wildlife Service (FSW) Acute Toxicity Rating Scale, all tested Nb-MXene nanosheets were classified as "Practically not toxic". However, DL-Nb4C3Tx should be treated with caution as it might cause a neurotoxic effect on fauna when it ends up in wastewater in high concentrations.

Raman spectroscopic quantification of graphene oxide in soil: Transport, surficial enrichment and environmental effects

The transport and retention data in environmental media are indispensable for the hazard evaluations of graphene materials. Due to the complexity of soil, the transport of graphene is hard to quantify without isotope labeling. Herein, we developed 2D Raman mapping as a label-free technique to quantify graphene oxide (GO) in soil. After pre-treatment by hydrazine hydrate to quench its fluorescence, the quantification of GO in soil was achieved in the range of 0.1-1000 mg/L by measuring the average G-band intensity. In column transport experiment, the transport and retention of GO in soil depended on the solution chemistry. Lower pH and higher ionic strength hindered the transport of GO. In particular, Ca2+ showed the most obvious retardation on the transport of GO. GO enriched in the surficial soil layer by several folds of the initial concentrations, and higher GO concentration led to more surficial enrichment. The sowing manner of seeds affected the soil enrichment of GO, too. The surficial enrichment of GO reduced its direct contact with seedling roots, resulting in the alleviation of GO toxicity. Our results provided a facile method to study the environmental behaviors of graphene and highlighted the crucial impacts of environmental media on the graphene toxicity.

Comparison of developmental toxicity of graphene oxide and graphdiyne to zebrafish larvae

Graphdiyne (GDY) is a new member of family of carbon-based 2D nanomaterials (NMs), but the environmental toxicity is less investigated compared with other 2D NMs, such as graphene oxide (GO). In this study, we compared with developmental toxicity of GO and GDY to zebrafish larvae. It was shown that exposure of zebrafish embryos from 5 h post fertilization to GO and GDY for up to 5 days decreased hatching rate and induced morphological deformity. Behavioral tests indicated that GO and GDY treatment led to hyperactivity of larvae. However, blood flow velocity was not significantly affected by GO or GDY. RNA-sequencing data revealed that both types of NMs altered gene expression profiles as well as gene ontology terms and KEGG pathways related with metabolism. We further confirmed that the NMs altered the expression of genes related with lipid droplets and autophagy, which may be account for the delayed development of zebrafish larvae. At the same mass concentrations, GO induced comparable or even larger toxic effects compared with GDY, indicating that GDY might be more biocompatible compared with GO. These results may provide novel understanding about the environmental toxicity of GO and GDY in vivo.

The addition of mammalian cell culture medium impacts nanoparticle toxicity in zebrafish

Engineered nanomaterials (ENMs) are ubiquitous in contemporary applications, yet their environmental and human health impacts remain inadequately understood. This study addresses the challenge of identifying potential risks associated with ENM exposure by highlighting the significant variability in existing research methodologies. Without a systematic collection of toxicological data that encompasses standardized materials, relevant platforms, and assays, the task of identifying potential risks linked to ENM exposure becomes an intricate challenge. In vitro assessments often use media rich in ionic species, such as RPMI and fetal bovine serum (FBS). Zebrafish embryos, known to develop normally in low-ionic environments, were exposed to Cerium Oxide, Zinc Oxide, and Graphene Oxides in different media at varying concentrations. Here, we discovered that zebrafish embryos tolerated a mix of 80 % RPMI, 2 % FBS, and 1 % antibiotic cocktail. The results revealed that adverse effects observed in zebrafish with certain nanomaterials in Ultra-Pure (UP) water were mitigated in cell culture medium, emphasizing the importance of revisiting previously considered non-toxic materials in vitro. The zebrafish results underscore the importance of utilizing a multidimensional in vivo platform to gauge the biological activity of nanomaterials accurately.

A comprehensive review on the progress and challenges of tetrahydroisoquinoline derivatives as a promising therapeutic agent to treat Alzheimer's disease

Alzheimer's disease (AD) is the most common and irreversible neurodegenerative disorder worldwide. While the precise mechanism behind this rapid progression and multifaceted disease remains unknown, the numerous drawbacks of the available therapies are prevalent, necessitating effective alternative treatment methods. In view of the rising demand for effective AD treatment, numerous reports have shown that tetrahydroisoquinoline (THIQ) is a valuable scaffold in various clinical medicinal molecules and has a promising potential as a therapeutic agent in treating AD due to its significant neuroprotective, anti-inflammatory, and antioxidative properties via several mechanisms that target the altered signaling pathways. Therefore, this review comprehensively outlines the potential application of THIQ derivatives in AD treatment and the challenges in imparting the action of these prospective therapeutic agents. The review emphasizes a number of THIQ derivatives, including Dauricine, jatrorrhizine, 1MeTIQ, and THICAPA, that have been incorporated in AD studies in recent years. Subsequently, a dedicated section of the review briefly discusses the emerging potential benefits of multi-target therapeutics, which lie in their ability to be integrated with alternative therapeutics. Eventually, this review elaborates on the rising challenges and future recommendations for the development of therapeutic drug agents to treat AD effectively. In essence, the valuable research insights of THIQ derivatives presented in this comprehensive review would serve as an integral reference for future studies to develop potent therapeutic drugs for AD research.

Brain targeted luteolin-graphene oxide nanoparticle abrogates polyethylene terephthalate induced altered neurological response in zebrafish

BACKGROUND

Polyethylene terephthalate (PET), a commonly used polymer in various food and plastic bag containers, has raised significant concerns regarding its environmental and human health risks. Despite its prevalent use, the impact of PET exposure on aquatic environments and its potential to induce neurotoxic conditions in species remain poorly understood. Furthermore, the mechanisms underlying amelioration through natural product intervention are not well-explored. In light of these gaps, our study aimed to elucidate the neurotoxic effects of PET in zebrafish through waterborne exposure, and to mitigate its neurological impact using luteolin-graphene oxide nanoparticles.

METHODS AND RESULTS

Our investigation revealed that exposure to PET in water triggered adverse effects in zebrafish larvae, particularly in the head region. We observed heightened oxidative stress, lipid peroxidation, and cell death, accompanied by impaired antioxidant defense enzymes. Furthermore, abnormal levels of acetylcholine esterase and nitric oxide in the zebrafish brain indicated cognitive impairment. To address these issues, we explored the potential neuroprotective effects of luteolin-graphene oxide nanoparticles. These nanoparticles demonstrated efficacy in localizing within the zebrafish brain, enhancing their therapeutic impact against PET exposure. Treatment with luteolin-graphene oxide nanoparticles not only mitigated PET-induced neurological alterations but also exhibited a neuroprotective effect. This was evidenced by the regulation of pro-inflammatory cytokine gene expression in the zebrafish brain. Additionally, normalization of locomotory behavior in PET-exposed zebrafish following nanoparticle treatment underscored the potential effectiveness of luteolin-graphene oxide nanoparticles as a treatment against PET-induced neurotoxicity.

CONCLUSIONS

In summary, our study emphasizes the urgent need to investigate the environmental and health risks associated with PET. We demonstrate the potential of luteolin-graphene oxide nanoparticles as an effective intervention against PET-induced neurotoxicity in zebrafish.

Cytotoxicity of Carbon Nanotubes, Graphene, Fullerenes, and Dots

The cytotoxicity of carbon nanomaterials is a very important issue for microorganisms, animals, and humans. Here, we discuss the issues of cytotoxicity of carbon nanomaterials, carbon nanotubes, graphene, fullerene, and dots. Cytotoxicity issues, such as cell viability and drug release, are considered. The main part of the review is dedicated to important cell viability issues. They are presented for A549 human melanoma, E. coli, osteosarcoma, U2-OS, SAOS-2, MG63, U87, and U118 cell lines. Then, important drug release issues are discussed. Bioimaging results are shown here to illustrate the use of carbon derivatives as markers in any type of imaging used in vivo/in vitro. Finally, perspectives of the field are presented. The important issue is single-cell viability. It can allow a correlation of the functionality of organelles of single cells with the development of cancer. Such organelles are mitochondria, nuclei, vacuoles, and reticulum. It allows for finding biochemical evidence of cancer prevention in single cells. The development of investigation methods for single-cell level detection of viability stimulates the cytotoxicity investigative field. The development of single-cell microscopy is needed to improve the resolution and accuracy of investigations. The importance of cytotoxicity is drug release. It is important to control the amount of drug that is released. This is performed with pH, temperature, and electric stimulation. Further development of drug loading and bioimaging is important to decrease the cytotoxicity of carbon nanomaterials. We hope that this review is useful for researchers from all disciplines across the world.