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Architected materials with nanoscale features have enabled extreme combinations of properties by exploiting the ultralightweight structural design space together with size-induced mechanical enhancement at small scales. Apart from linear waves in metamaterials, this principle has been restricted to quasi-static properties or to low-speed phenomena, leaving nanoarchitected materials under extreme dynamic conditions largely unexplored. Here, using supersonic microparticle impact experiments, we demonstrate extreme impact energy dissipation in three-dimensional nanoarchitected carbon materials that exhibit mass-normalized energy dissipation superior to that of traditional impact-resistant materials such as steel, aluminium, polymethyl methacrylate and Kevlar. In-situ ultrahigh-speed imaging and post-mortem confocal microscopy reveal consistent mechanisms such as compaction cratering and microparticle capture that enable this superior response. By analogy to planetary impact, we introduce predictive tools for crater formation in these materials using dimensional analysis. These results substantially uncover the dynamic regime over which nanoarchitecture enables the design of ultralightweight, impact-resistant materials that could open the way to design principles for lightweight armour, protective coatings and blast-resistant shields for sensitive electronics. Nanoarchitected materials have predominantly been studied in the quasi-static regime. Here, the supersonic microparticle impact regime for three-dimensional nanomaterials is uncovered, showcasing extreme energy dissipation and a predictive framework for damage.

Photopolymer resins are widely used in the production of dental prostheses, but their mechanical properties require improvement. We evaluated the effects of different zirconia filler contents and printing directions on the mechanical properties of photopolymer resin. Three-dimensional (3D) printing was used to fabricate specimens using composite photopolymers with 0 (control), 3, 5, and 10 wt.% zirconia filler. Two printing directions for fabricating rectangular specimens (25 mm × 2 mm × 2 mm) and disk-shaped specimens (φ10 mm × 2 mm) were used, 0° and 90°. Three-point bending tests were performed to determine the flexural strengths and moduli of the specimens. The Vickers hardness test was performed to determine the hardness of the specimens. Tukey’s multiple comparison tests were performed on the average values of the flexural strengths, elastic moduli, and Vickers hardness after one-way ANOVA (α = 0.05). The flexural strengths and elastic moduli at 0° from high to low were in the order of 0, 3, 10, and 5 wt.%, and those at 90° were in the order of 3, 0, 10, and 5 wt.% (p < 0.05). For 5 and 10 wt.%, no significant differences were observed in mechanical properties at 0° and 90° (p < 0.05). The Vickers hardness values at 0° and 90° from low to high were in the order of 0, 3, 5, and 10 wt.% (p < 0.05). Within the limits of this study, the optimal zirconia filler content in the photopolymer resin for 3D printing was 0 wt.% at 0° and 3 wt.% at 90°.

Polymethyl methacrylate (PMMA)-based bone cement is a biomaterial that has been used over the last 50 years to stabilize hip and knee implants or as a bone filler. Although PMMA-based bone cement is widely used and allows a fast-primary fixation to the bone, it does not guarantee a mechanically and biologically stable interface with bone, and most of all it is prone to bacteria adhesion and infection development. In the 1970s, antibiotic-loaded bone cements were introduced to reduce the infection rate in arthroplasty; however, the efficiency of antibiotic-containing bone cement is still a debated issue. For these reasons, in recent years, the scientific community has investigated new approaches to impart antibacterial properties to PMMA bone cement. The aim of this review is to summarize the current status regarding antibiotic-loaded PMMA-based bone cements, fill the gap regarding the lack of data on antibacterial bone cement, and explore the progress of antibacterial bone cement formulations, focusing attention on the new perspectives. In particular, this review highlights the innovative study of composite bone cements containing inorganic antibacterial and bioactive phases, which are a fascinating alternative that can impart both osteointegration and antibacterial properties to PMMA-based bone cement.

Plastics, ubiquitous in daily life and industry, are released into the environment in substantial quantities. Instead of complete biodegradation, plastic waste fragments into smaller particles, accumulating as nanoplastics (NPs; < 1 μm). Humans are exposed to NPs through inhalation and ingestion of contaminated water and food, which can induce cytotoxicity through physical and chemical pathways. Polymethyl methacrylate (PMMA), commonly used in implants and artificial bones, has been identified in human lungs and associated with pulmonary embolism. While PMMA NP toxicity has been reported in vitro, their in vivo effects, as well as the underlying mechanism, remain poorly understood. In this study, we investigated the pulmonary effects of inhaled PMMA NPs in mice. Mice received 20 or 100 μg of PMMA NPs (25 nm) via intratracheal intubation for 28 days. PMMA-NP preparation and characterization are described in the Methods section. Exposed mice exhibited body weight loss and pulmonary accumulation of PMMA NPs. Bronchoalveolar lavage fluid (BALF) analysis revealed increased cell count and elevated inflammatory cytokines in serum and BALF. Histopathology (H&E staining) revealed abnormalities in lung tissue and alterations in protein and RNA expression. The findings demonstrate that respiratory exposure to PMMA NPs induces lung inflammation, tissue damage, and molecular dysregulation.

Polymethyl methacrylate (PMMA) is widely used in modern dentistry, particularly in prosthodontics, orthodontics, and maxillofacial surgery. To improve the properties of PMMA, silver nanoparticles (AgNPs) are incorporated to enhance the antibacterial, antiviral, and antifungal effects of this material. This study aims to evaluate the antimicrobial properties of AgNPs as an additive to PMMA. Medical databases covered by the ACM, BASE, PubMed, and Scopus engines were searched. Of the 670 identified records, 23 studies were included that assessed the antibacterial and antifungal properties gained by incorporating AgNPs into PMMA. All of the studies included also contained a control group-PMMA without additives. Studies that evaluated nanoparticles other than AgNPs or materials other than PMMA were excluded. The data collected from the articles included the size and concentration of the nanoparticles, the method of sample preparation, sample size, information on the effect of nanoparticles on antimicrobial properties, and the contact time between the sample and the test tube containing fungi or bacteria. The data were presented in tables and graphs. The analysis indicated that increasing the weight percent concentration of AgNPs or extending the incubation time increases the antifungal efficacy. The result of Tau Kendall correlation showed that the pairs of data, concentration/incubation time and outcomes, are inversely proportional for fungi ( < 0.01). The results of the study are not entirely conclusive. Some limitations suggest the need for more standardized studies, which ideally should be conducted on human research groups and followed by a study of these properties and their effects on the human body. This systematic review followed PRISMA 2020 guidelines. The protocol was submitted to the Open Science Framework Registries (1 December 2024).

The fabrication of ternary nanocomposites attracts great interest in scientific research worldwide. PVC/PMMA/AgO nanocomposites are prepared by the casting method with various proportions of AgONPs. Analysis of XRD and FTIR spectra exhibited that the structural parameters of PVC/PMMA blend have been affected with increasing nanofiller content. UV–Vis spectra analysis showed that the direct/indirect energy gap are decreased from (5.21/4.92) to (4.86/3.90) eV and the dispersion and oscillation ( E d /E o ) energies are increased from (1.186/4.437) to (73.323/13.638) eV with increasing the content of AgONPs. Linear/nonlinear optical parameters of PVC/PMMA/AgO nanocomposites are enhanced upon increasing AgONPs content. This study also showed that the antibacterial activity of PVC/PMMA/AgO nanocomposites against Gram-positive bacteria ( S. aureus, B. subtilis ) and Gram-negative bacteria ( E. coli) is enhanced. Generally, PVC/PMMA/AgO nanocomposites show promising potential in the field of flexible optoelectronic devices due to the structure-dependent adjustable optical energy gap and in the medical field for their pronounced antibacterial activity.

Silicon dioxide (SiO ) nanoparticles approximately 5 nm in size have been obtained. A method has been developed for introducing SiO nanoparticles into photolithographic resin at concentrations up to 0.1%. Composite resins can be used to manufacture parts with complex geometries with a maximum achievable resolution of 50 μm. Parts made from composite resin with SiO nanoparticles polish well. After polishing, areas of approximately 100 μm with height differences of less than 10 nm are revealed on the surface of the parts. A relatively uniform distribution of SiO nanoparticles is observed within the parts, and no optical defects are detected. However, areas differing in the phase shift of electromagnetic radiation are observed within the parts. Importantly, the presence of nanoparticles in the resin during MSLA printing increases the degree of resin polymerization. SiO nanoparticles have been shown to have prooxidant properties, leading to the formation of 8-oxoguanine in DNA and long-lived reactive protein species. Components made from photolithographic resins with SiO nanoparticles have been shown to inhibit the growth and development of bacteria, with a significant loss of viability. Despite their antimicrobial properties, components made from photolithographic resins with SiO nanoparticles do not affect the growth and development of mammalian cells.

Poly (methyl methacrylate) (PMMA) bone cement is widely used in percutaneous vertebroplasty to stabilize osteoporotic vertebral compression fractures. However, its clinical application is limited by its high compressive modulus, risk of thermal necrosis, and poor bone integration, unlike conventional PMMA formulations used in vertebrae or joint arthroplasty, which can reach polymerization temperatures exceeding 100 °C. Spine-specific PMMA is formulated to cure at a reduced polymerization temperature, thereby minimizing the rise in core temperature during the setting process. Consistent with our hypothesis, this moderate thermal output induces localized thermal injury that triggers osteogenic responses and extracellular matrix production, thereby enhancing osteoblast activity in the surrounding bone. This study aimed to evaluate bone remodeling following spine-specific PMMA injection in an osteoporotic Sprague-Dawley (SD) rat model. Twenty-four osteoporotic female SD rats were randomly assigned to three groups: Control (untreated), OVX + spine-specific PMMA (OVX + PMMA), and OVX (OVX + Defect). Bone regeneration was assessed using dual-energy X-ray absorptiometry (DXA), micro-computed tomography (Micro-CT), quantitative PCR (qPCR), immunohistochemistry (IHC), and Western blotting. At 12 weeks post-injection, the OVX + PMMA group exhibited significantly greater bone regeneration than the OVX group. Micro-CT analysis demonstrated a marked increase in trabecular thickness in the PMMA-treated group. Notably, bone formation was more pronounced in regions surrounding the cement compared to adjacent untreated areas. This suggests that spine-specific PMMA promotes osteogenesis via localized thermal necrosis and subsequent osteoblast recruitment. These findings highlight the dual role of spine-specific PMMA in both structural stabilization and biologically driven bone regeneration. Further research is warranted to optimize its clinical applications while minimizing potential adverse effects.

This study investigates various microfluidic chip fabrication techniques, highlighting their applicability and limitations in the context of urgent diagnostic needs showcased by the COVID-19 pandemic. Through a detailed examination of methods such as computer numerical control milling of a polymethyl methacrylate, soft lithography for polydimethylsiloxane-based devices, xurography for glass-glass chips, and micromachining-based silicon-glass chips, we analyze each technique’s strengths and trade-offs. Hence, we discuss the fabrication complexity and chip thermal properties, such as heating and cooling rates, which are essential features of chip utilization for a polymerase chain reaction. Our comparative analysis reveals critical insights into material challenges, design flexibility, and cost-efficiency, aiming to guide the development of robust and reliable microfluidic devices for healthcare and research. This work underscores the importance of selecting appropriate fabrication methods to optimize device functionality, durability, and production efficiency.

Research on the uptake and effects of bioplastics by aquatic organisms is still in its infancy. Here, we aim to advance the field by comparing uptake and effects of microplastic particles (MPP) of a biodegradable bioMPP (polyhydroxybutyrate (PHB)) and petroleum-based MPP (polymethylmethacrylate (PMMA)) in the freshwater amphipod Gammarus fossarum. Ingestion of both MPP in different particle sizes (32–250 µm) occurred after 24 h, with highest ingestion of particles in the range 32–63 µm and almost complete egestion after 64 h. A four-week effect-experiment showed a significant decrease of the assimilation efficiency in amphipods exposed to the petroleum-based MPP from week two onwards. The petroleum-based PMMA affected assimilation efficiency significantly in contrast to the biodegradable PHB, but overall differences in direct comparison of MPP types were small. Both MPP types led to a significantly lower wet weight gain relative to the control treatments. After four weeks, differences between both MPP types and silica, used as a natural particle control, were detected. In summary, these results suggest that both MPP types provoke digestive constraints on the amphipods, which go beyond those of natural non-palatable particles. This highlights the need for more detailed research comparing environmental effects of biodegradable and petroleum-based MPP and testing those against naturally occurring particle loads.