Beilstein Journal of Nanotechnology最新文献

The widespread use of plastic has led to microplastics (MPs) being released in many water sources. MP contamination in water supply systems is a global concern due to their persistence and ability to adsorb toxic pollutants. Despite having effectiveness, conventional water treatment processes still have limited efficiency in removing MPs, especially smaller particles. Thus, it requires researchers to develop effective and sustainable strategies to deal with this matter. Many studies have shown that adsorbent nanomaterials have potential for the removal of MPs from water. This review evaluates the current status of using adsorbent nanomaterials in removing MPs from water supply systems. It discusses the occurrences and removal efficiency of MPs in water supply systems, as well as the mechanisms and performance when applying these materials for treatment. In addition, the related risk of adsorbent nanomaterials is also considered. Microplastics from land-based sources and wastewater plants persist in water supplies, with conventional treatments removing only 40-70%, especially struggling with smaller particles. Based mainly on mechanisms like electrostatic interactions, hydrophobic interactions, pore filling, hydrogen bonding, π-π stacking, and surface complexation, adsorbent nanomaterials achieve over 90% removal of MPs and can recovery. Their effectiveness depends on material properties and environmental factors, but challenges remain in scale-up and related risks. Adsorbent nanomaterials show promising potential to enhance MP removal through specific properties. Although some related risks are discussed, these materials provide a foundation for developing sustainable, effective solutions to mitigate MPs pollution in the water supply system.

Recent research in alternate sources of energy such as piezoelectric energy conversion devices has positioned layered double hydroxides (LDHs) as promising candidates among the other two-dimensional materials. With their unique flexible layered structure, LDHs hold great potential for piezocatalysis and powering smart wearable electronics. Despite their promise, this area of study is still in its infancy and this review explores its recent advances. The discussion encompasses LDH-based piezoelectric nanogenerators, piezocatalytic and piezo-photocatalytic properties of LDHs, and composite material synergies that enhance the overall electroactive performance. Looking to the future, systematic research into the effects of LDHs' composition and structure on piezoelectric properties will be crucial to unlock their full potential. This mini-review aims to inspire the audience with valuable ideas for the development of new LDH-based piezoelectric materials, thereby contributing to the development of next-generation high-performance piezoelectric devices.

It was recently shown that small bundles of linear carbon chains (LCC) encapsulated by double- and multi-wall carbon nanotubes (LCC@DWCNT and LCC@MWCNT, respectively) behave as Debye's materials for temperatures as high as 293 K with an estimate that such materials could still withstand such characteristics for even higher temperatures (≈700 K). Using the Debye model, thermodynamic observables (internal energy, coefficient of linear thermal expansion, specific heat, thermal strain, and Grüneisen parameter at constant pressure) were empirically determined for the first time in the range of temperatures 70 < T < 293 K. These observables were all correlated with the C-band frequency (ω_LCC) dependence on the temperature (T) and its first and second derivatives with relation to T, dω_LCC/dT, and d²ω_LCC/dT ². The C-band is a Raman spectroscopic signature for LCC, which is not only temperature-dependent but also dependent on the number of carbon atoms (N) constituting the LCC. In this present study, we extend these findings to temperatures ranging from 13 < T < 293 K, which provide more accurate values for both dω_LCC/dT and d²ω_LCC/dT ². The corrected values of these derivatives affect the Grüneisen parameters associated with the LCC, even though the other associated thermodynamic parameters remain essentially unchanged. Our measurements were performed in both isolated and small bundles of LCC@MWCNT, which allowed us to demonstrate that small bundles or isolated environments do not seem to influence the vibrational and thermodynamic properties measured.

Precise control of electrical conductivity, humidity sensitivity, and photocatalytic activity in polymeric and carbon-based materials is essential for advancing technologies in environmental sensing, flexible electronics, and photocatalytic systems. Conventional chemical modification methods often lack spatial precision, introduce impurities, and risk structural degradation. Ion implantation provides a controllable alternative for tuning surface properties at the nanoscale, enabling the targeted introduction of functional species without chemical reagents. This work investigates the effects of low-energy (20 keV) and medium-energy (1.5 MeV) Ag⁺ ion implantation on the electrical, sensory, and photocatalytic properties of graphene oxide (GO) and polyimide (PI). Implantations were carried out with fluences ranging from 3.75 × 10¹² cm^-2 to 1 × 10¹⁶ cm^-2. Silver ions offer excellent electrical, catalytic, and plasmonic characteristics, making them ideal for multifunctional enhancement of GO and PI. Elemental and structural changes induced by implantation were analyzed using Rutherford backscattering spectroscopy, elastic recoil detection analysis, Raman spectroscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Surface morphology was assessed via atomic force microscopy. Electrical properties as a function of air humidity were evaluated using a two-point method, and photocatalytic activity was tested by monitoring the UV-induced decomposition of rhodamine B. The results demonstrate that ion implantation significantly reduces surface resistivity and enhances both the photocatalytic activity and humidity sensitivity of GO and PI. The most pronounced improvements occurred at higher fluences, where defect generation and partial deoxygenation contributed to optimal performance. Ion implantation thus represents an effective approach for tuning the multifunctional behavior of polymer systems.

Polymers play a pivotal role in various drug delivery systems due to their versatility, with polymeric nanoparticles showing significant potential to overcome physiological barriers associated with oral administration. This review examines the current advancements in the application of polymers as oral nanocarriers, emphasizing key natural and synthetic polymers that enhance stability, bioavailability, and release. The physicochemical properties, biodegradability, and chemical modifications of these polymers, which promote mucoadhesion and epithelial permeability, critical factors for effective oral drug delivery, are discussed in detail. Furthermore, nanoparticle synthesis methods that enable controlled release profiles, optimized biodistribution, and improved therapeutic efficacy are also explored. Thus, polymers represent a dynamic platform for developing diverse nanocarriers for oral applications, and this review provides a valuable theoretical foundation for understanding the strategies currently employed in this field.

Esophageal cancer (EC) is a common malignant tumor of the digestive tract with poor prognosis and high mortality. The early diagnosis of EC mainly depends on endoscopic diagnosis, which not only needs to bear certain economic pressure, but also needs patients to recognize the high risk factors of EC. Most EC patients are diagnosed at intermediate or late stages, often due to a lack of awareness regarding early symptoms and lifestyle-related risk factors. However, the discovery of aptamers and the development of nanocarriers bring great benefits to the diagnosis, treatment, and targeted drug delivery of EC. Aptamers or peptide aptamers as biosensors or therapeutic agents for the diagnosis or treatment of EC, aptamer-drug conjugates and aptamer-functionalized drug nanocarriers for targeted drug delivery in esophageal cancer are reviewed in this paper. In addition, we expect investigators to pay special attention to improving aptamer permeability and stability to accelerate aptamer clinical transformation. In conclusion, leveraging the high target specificity of well-selected aptamers may bring new breakthroughs in the diagnosis, treatment and drug delivery of EC.

The treatment of dry eye disease (DED) often requires frequent use of artificial tear products. Because of their low permeability and limited ocular bioavailability, repeated applications are required for therapeutic effectiveness. In contrast to traditional drug delivery systems (DDS), a functional ophthalmic nanoemulsion was specifically designed to alleviate symptoms of DED by leveraging its antioxidant and osmoprotective properties. The study evaluated the optimal concentration of lecithin required to produce nanoemulsions with a uniform particle size and incorporated a co-surfactant to enhance the stability of the nanoformulation. A straightforward method was proposed, involving the dilution of the preformulation in an ophthalmic vehicle, followed by homogenization through ultrasonication, resulting in OphtNE-3.70% with a droplet diameter of 173 nm and a zeta potential of -44.7 mV. The addition of Kolliphor^® HS15 in OphtNE-3.66%(K1%) initially reduced the droplet size to 70.8 nm and enhanced the antioxidant effect. Although the droplet size and polydispersity index increased after more than 60 days, the formulation remained physically quite stable without phase separation. Both nanoformulations contained 2.6% (w/v) linseed oil, providing a bioactive concentration compatible with ocular administration volumes (~50 µL). At a final concentration of 1.30 mg·mL^-1, OphtNE-3.66%(K1%) showed >75% cell viability in L929 cells and ~10% 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant effect. These findings support the multifunctional potential (cytocompatibility and antioxidant) of sterile OphtNE-3.66%(K1%) for the treatment of DED, emphasizing the need for in vivo studies to ensure its efficacy and safety for ocular administration.

The anisotropic hygroscopic behavior of pine cone scales and its effect on bending motion, with implications for bioinspired actuation, is investigated. Using gravimetric water uptake measurements, synchrotron radiation-based nano-holotomography, and digital volume correlation analysis, inter- and intra-tissue variations of hygroscopic swelling/shrinkage were observed. In addition, the moisture content of pine cone scale tissues was measured as a function of relative humidity. There were distinct differences between tissues and a pronounced hysteresis between sorption and desorption. Finite element analysis was performed on geometries ranging from simplified bilayer models to complex remodeled scales. Simulation results showed an underestimation of the bending of bilayer geometries due to an overestimated contribution of sclerenchyma fiber stiffness. Geometries with discrete fibers embedded in a brown tissue matrix more accurately reproduced the bending angles observed in experiments. This highlights the importance of the chosen material properties and tissue arrangements for predicting pine cone scale bending in silico. By contributing to a deeper understanding of pine cone scale biomechanics, these results also support the development of bioinspired technical applications. Future studies should refine tissue mechanical properties and integrate high-resolution computed tomography-based geometries to further elucidate the mechanisms underlying hygroscopic actuation. This integrative approach will bridge experimental findings with computational modeling and advance plant biomechanics and biomimetic transfer.

In this work we consider a spin model composed of a single spin and connected to an infinitely coordinated Ising chain. Theoretical models of this type arise from various fields of theoretical physics, such as theory of open systems, quantum control, and quantum computations. In the thermodynamic limit of an infinite chain, we map the chain Hamiltonian to the Hamiltonian of the Lipkin-Meshkov-Glik model, and the system as a whole is described by a generalized Rabi Hamiltonian. Next, the effective Hamiltonian is obtained using the Foulton-Gouterman transformation. In the thermodynamic limit we obtain the spectrum of the whole system and study the properties of the ground-state quantum phase transition.

Ambient pressure X-ray photoelectron spectroscopy (APXPS) has emerged as an important technique for investigating surface and interface chemistry under realistic conditions, overcoming the limitations of conventional XPS restricted to ultrahigh vacuum. This review highlights the capabilities and scientific impact of APXPS at the MAX IV Laboratory, the world's first fourth-generation synchrotron light source. With the APXPS beamlines SPECIES and HIPPIE, MAX IV offers state-of-the-art instrumentation for in situ and operando studies across a broad pressure range, enabling research in catalysis, corrosion, energy storage, and thin film growth. The high brilliance and small beam size of MAX IV's synchrotron light are essential for pushing the time-resolution boundaries of APXPS, especially in the soft X-ray regime. We discuss representative studies at MAX IV, including investigations of single-atom catalysts, confined catalysis, time-resolved catalysis, atomic layer deposition, and electrochemical interfaces, showcasing the role of APXPS in advancing material and surface science.