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oe1(光电查) - 科学论文

52 条数据
?? 中文(中国)
  • Biodissolution and cellular response to MoO <sub/>3</sub> nanoribbons and a new framework for early hazard screening for 2D materials

    摘要: Two-dimensional (2D) high-aspect-ratio sheet-like materials are a broad class of synthetic ultra-thin sheet-like solids whose rapid pace of development motivates systematic study of their biological effects and safe design. A challenge for this effort is the large number of new materials and their chemical diversity. Recent work suggests that many 2D materials will be thermodynamically unstable and thus non-persistent in biological environments. Such information could inform and accelerate safety assessment, but experimental data to confirm the thermodynamic predictions are lacking. Here we propose a framework for early hazard screening of nanosheet materials based on biodissolution studies in reactive media, specially chosen for each material to match chemically feasible degradation pathways. Simple dissolution and in vitro tests allow grouping of nanosheet materials into four classes: A, potentially biopersistent; B, slowly degradable (>24–48 hours); C, biosoluble with potentially hazardous degradation products; and D, biosoluble with low-hazard degradation products. The proposed framework is demonstrated through an experimental case study on MoO3 nanoribbons, which have a dual 2D/1D morphology and have been reported to be stable in aqueous stock solutions. The nanoribbons are shown to undergo rapid dissolution in biological simulant fluids and in cell culture, where they elicit no adverse responses up to 100 μg ml?1 dose. These results place MoO3 nanoribbons in Class D, and assigns them a low priority for further nanotoxicology testing. We anticipate use of this framework could accelerate the risk assessment for the large set of new powdered 2D nanosheet materials, and promote their safe design and commercialization.

    关键词: 2D materials,nanosheets,cytotoxicity,hazard screening,biodissolution,MoO3 nanoribbons

    更新于2025-09-04 15:30:14

  • Effect of Polyethylene Glycol Surface Charge Functionalization of SWCNT on the in vitro and in vivo Nanotoxicity and Biodistribution Monitored Noninvasively using MRI

    摘要: The current study evaluated in vitro and in vivo toxicity of carboxyl or amine PEG surface functionalization of single walled carbon nanotubes (SWCNTs). Assessments of cytotoxicity, genotoxicity, immunotoxicity and oxidative stress were performed in vitro and in vivo (in a one-month follow-up study). The SWCNT biodistribution was investigated using noninvasive MRI. Results confirmed the enhanced biocompatibility of PEG-functionalized SWCNTs compared to non-functionalized materials with significant decreases (p<0.05) in the percentage of cell viability and increases in ROS generation, mitochondrial membrane potential, cell apoptosis, oxidative stress generation and oxidative DNA damage in vitro. PEG-functionalized SWCNTs with amine terminals were found to induce prominent increases in ROS generation, mitochondrial membrane potential, and oxidative stress compared to carboxy functionalized SWCNTs. No significant difference in the biodistribution of either PEG-COOH or PEG-NH2 functionalized SWCNTs was observed in MRI. In vivo assessments revealed a statistically significant increase (p<0.05) in oxidative stress as early as 24 h in serum and liver; however, all values normalized at 2 weeks’ investigation time point. DNA damage was minimal with either PEG-COOH or PEG-NH2 functionalized SWCNTs after two weeks’ exposure. The negatively charged SWCNTs caused lesser DNA damage compared to positively charged samples. Carboxy-functionalized SWCNTs did not caused substantial changes in inflammatory mediators and were found to be significantly safer than non-functionalized SWCNTs and may pave the way for novel biomedical applications in cancer diagnosis and therapy.

    关键词: Nanotoxicity,Cytotoxicity,Carbon nanotubes,In vivo biodistribution,Magnetic Resonance Imaging

    更新于2025-09-04 15:30:14