Toward an operational methodology to identify industrial-scaled nanomaterial powders with the volume specific surface area criterion

Identification of a Gene Signature Predicting (Nano)Particle-Induced Adverse Lung Outcome in Rats

Nanoparticles are extensively used in industrial products or as food additives. However, despite their contribution to improving our quality of life, concerns have been raised regarding their potential impact on occupational and public health. To speed up research assessing nanoparticle-related hazards, this study was undertaken to identify early markers of harmful effects on the lungs. Female Sprague Dawley rats were either exposed to crystalline silica DQ-12 with instillation, or to titanium dioxide P25, carbon black Printex-90, or multi-walled carbon nanotube Mitsui-7 with nose-only inhalation. Tissues were collected at three post-exposure time points to assess short- and long-term effects. All particles induced lung inflammation. Histopathological and biochemical analyses revealed phospholipid accumulation, lipoproteinosis, and interstitial thickening with collagen deposition after exposure to DQ-12. Exposure to the highest dose of Printex-90 and Mitsui-7, but not P25, induced some phospholipid accumulation. Comparable histopathological changes were observed following exposure to P25, Printex-90, and Mitsui-7. Comparison of overall gene expression profiles identified 15 potential early markers of adverse lung outcomes induced by spherical particles. With Mitsui-7, a distinct gene expression signature was observed, suggesting that carbon nanotubes trigger different toxicity mechanisms to spherical particles.

NanoDefiner Framework and e-Tool Revisited According to the European Commission's Nanomaterial Definition 2022/C 229/01

The new recommended definition of a nanomaterial, 2022/C 229/01, adopted by the European Commission in 2022, will have a considerable impact on European Union legislation addressing chemicals, and therefore tools to implement this new definition are urgently needed. The updated NanoDefiner framework and its e-tool implementation presented here are such instruments, which help stakeholders to find out in a straightforward way whether a material is a nanomaterial or not. They are two major outcomes of the NanoDefine project, which is explicitly referred to in the new definition. This work revisits the framework and e-tool, and elaborates necessary adjustments to make these outcomes applicable for the updated recommendation. A broad set of case studies on representative materials confirms the validity of these adjustments. To further foster the sustainability and applicability of the framework and e-tool, measures for the FAIRification of expert knowledge within the e-tool's knowledge base are elaborated as well. The updated framework and e-tool are now ready to be used in line with the updated recommendation. The presented approach may serve as an example for reviewing existing guidance and tools developed for the previous definition 2011/696/EU, particularly those adopting NanoDefine project outcomes.

Mechanical Performance and Applications of CNTs Reinforced Polymer Composites-A Review

Developments in the synthesis and scalable manufacturing of carbon nanomaterials like carbon nanotubes (CNTs) have been widely used in the polymer material industry over the last few decades, resulting in a series of fascinating multifunctional composites used in fields ranging from portable electronic devices, entertainment and sports to the military, aerospace, and automotive sectors. CNTs offer good thermal and electrical properties, as well as a low density and a high Young's modulus, making them suitable nanofillers for polymer composites. As mechanical reinforcements for structural applications CNTs are unique due to their nano-dimensions and size, as well as their incredible strength. Although a large number of studies have been conducted on these novel materials, there have only been a few reviews published on their mechanical performance in polymer composites. As a result, in this review we have covered some of the key application factors as well as the mechanical properties of CNTs-reinforced polymer composites. Finally, the potential uses of CNTs hybridised with polymer composites reinforced with natural fibres such as kenaf fibre, oil palm empty fruit bunch (OPEFB) fibre, bamboo fibre, and sugar palm fibre have been highlighted.

Point-of-Care Diagnostics: Molecularly Imprinted Polymers and Nanomaterials for Enhanced Biosensor Selectivity and Transduction

Significant healthcare disparities resulting from personal wealth, circumstances of birth, education level, and more are internationally prevalent. As such, advances in biomedical science overwhelmingly benefit a minority of the global population. Point-of-Care Testing (POCT) can contribute to societal equilibrium by making medical diagnostics affordable, convenient, and fast. Unfortunately, conventional POCT appears stagnant in terms of achieving significant advances. This is attributed to the high cost and instability associated with conventional biorecognition: primarily antibodies, but nucleic acids, cells, enzymes, and aptamers have also been used. Instead, state-of-the-art biosensor researchers are increasingly leveraging molecularly imprinted polymers (MIPs) for their high selectivity, excellent stability, and amenability to a variety of physical and chemical manipulations. Besides the elimination of conventional bioreceptors, the incorporation of nanomaterials has further improved the sensitivity of biosensors. Herein, modern nanobiosensors employing MIPs for selectivity and nanomaterials for improved transduction are systematically reviewed. First, a brief synopsis of fabrication and wide-spread challenges with selectivity demonstration are presented. Afterward, the discussion turns to an analysis of relevant case studies published in the last five years. The analysis is given through two lenses: MIP-based biosensors employing specific nanomaterials and those adopting particular transduction strategies. Finally, conclusions are presented along with a look to the future through recommendations for advancing the field. It is hoped that this work will accelerate successful efforts in the field, orient new researchers, and contribute to equitable health care for all.

Identification of nanomaterials by the volume specific surface area (VSSA) criterion: application to powder mixes

We demonstrate the relevance of the Volume Specific Surface Area (VSSA) parameter to identify the nanoparticulate character of powder mixes based on either spherical constituent particles with bimodal size distributions (TiO2), or fiber-like constituent particles with unimodal size distributions (sepiolite and sepiolite-based pigments). These new results indicate that VSSA could reasonably be proposed as an optional criterion in the future for the definition of nanomaterials based on the European Commission recommendation, provided certain requirements are fulfilled.

Health and Safety Concerns Related to CNT and Graphene Products, and Related Composites

The use of Carbon Nanotubes (CNT) and Graphene increased in the last decade and it is likely to keep increasing in the near future. The attractiveness of their properties, particularly the possibility to enhance the composites performance using a tailor made methodology, brings new materials, processes and products for highly demanding industrial applications and to the market. However, there are quite a lot of health/safety issues, as well as lack of understanding and standards to evaluate their effects. This paper starts with a general description of materials, processes and products dealing with CNT and graphene. Then, an overview of concerns related to the health and safety when handling, researching, producing and using products that include these materials is presented. It follows a risk management approach with respect to simulation and evaluation tools, and considering the consensual limits already existing for research, industry and consumers. A general discussion integrating the relevant aspects of health and safety with respect to CNT and graphene is also presented. A proactive view is presented with the intention to contribute with some guidelines on installation, maintenance, evaluation, personal protection equipment (PPE) and personnel training to deal with these carbon-based nanomaterials in research, manufacture, and use with composite materials.

NanoDefiner e-Tool: An Implemented Decision Support Framework for Nanomaterial Identification

The European Commission's recommendation on the definition of nanomaterial (2011/696/EU) established an applicable standard for material categorization. However, manufacturers face regulatory challenges during registration of their products. Reliable categorization is difficult and requires considerable expertise in existing measurement techniques (MTs). Additionally, organizational complexity is increased as different authorities' registration processes require distinct reporting. The NanoDefine project tackled these obstacles by providing the NanoDefiner e-tool: A decision support expert system for nanomaterial identification in a regulatory context. It provides MT recommendations for categorization of specific materials using a tiered approach (screening/confirmatory), and was constructed with experts from academia and industry to be extensible, interoperable, and adaptable for forthcoming revisions of the nanomaterial definition. An implemented MT-driven material categorization scheme allows detailed description. Its guided workflow is suitable for a variety of user groups. Direct feedback and explanation enable transparent decisions. Expert knowledge is held in a knowledge base for representation of MT performance criteria and physicochemical particle type properties. Continuous revision ensured data quality and validity. Recommendations were validated by independent case studies on industry-relevant particulate materials. Besides supporting material identification and registration, the free and open-source e-tool may serve as template for other expert systems within the nanoscience domain.