Nanozymes, which are nanomaterials that mimic enzyme activity, offer compelling advantages like low cost, high activity, long-term stability, and easy surface modification. Among these, graphene quantum dots (GQDs) are particularly promising for diverse sensing applications due to their unique optical and electronic properties. Their inherent small size and the chemistry of their functional groups further enhance their catalytic capabilities. Accurately and sensitively detecting NADPH, which is a high-energy electron carrier for various metabolic processes, is crucial for gaining a deeper understanding of fundamental cellular function.

In this study, we successfully synthesized a GQD-based nanozyme. The synthesis involved a hydrothermal process (200 ^oC for 12 hours) using a hydrophilic polyethyleneimine (PEI) precursor doped with hemin. Comprehensive characterization with UV-Vis, energy-dispersive spectroscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy confirmed the successful formation of the nanomaterial. These analyses revealed an average diameter of 7.1 ± 1.5 nm for the synthesized GQDs, with a distinct excitation peak at 360 nm and an emission peak at 460 nm. Furthermore, elemental analysis confirmed the successful incorporation of both iron and nitrogen into the GQD structure, which is indicated by the presence of carbon, nitrogen, oxygen, and iron. The observed fluorescence quenching of this GQD nanozyme upon its interaction with NADPH clearly demonstrates its promising potential for sensitive and accurate NADPH detection, with a strong potential for targeted applications in detecting oxidative stress, which is essential for research in neurovascular health and metabolic diseases.

Water pollution is a global issue that affects many countries. In urban areas, water often becomes contaminated as a result of industrialization and may be saturated with organic pollutants, such as dyes like methylene blue. This contaminated water poses significant health risks to both humans and animals, contributing to environmental degradation. Thus, it is essential to properly treat water and remove these organic dyes before they are released into the ecosystem. Photodegradation is a chemical oxidation process that uses nanoparticles to effectively break down stable organic dyes, such as methylene blue. This study investigates CuO and Ag-doped CuO nanoparticles (NPs) synthesized using Flourensia cernua extract, focusing on their synthesis, physicochemical characteristics, and photocatalytic activity under sunlight. Green synthesis methods utilizing plant extracts offer environmentally benign routes for nanoparticle fabrication, attracting significant interest across multiple fields. The NPs were synthesized at varying temperatures, ranging from 300 to 600 °C, and characterized using X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), and transmission electron microscopy (TEM). The XRD patterns confirmed a monoclinic phase of CuO and the formation of Ag/CuO heterostructures in all the samples. TEM micrographs showed irregularly shaped nanoparticles with sizes below 30 nm. The results of the photocatalytic activity indicate that increasing Ag content accelerates the degradation of methylene blue.

Four series of composite dielectric nanofluids were developed using a vegetable-based dielectric oil matrix doped with titanium dioxide (TiO₂) nanoparticles at concentrations of 0.5, 1.0, 3.0, and 5.0 wt%. The objective was to investigate the effects of nanoparticle content on the rheological, thermal, and colloidal stability properties of the nanofluids for potental use in electrical transformers. Rheological characterizaton was performed using amplitude and frequency sweep tests to determine viscosity, linear viscoelastic range (LVER), storage modulus (G′), and loss modulus (G″). The nanofluids exhibited concentration-dependent changes in viscoelastic behavior, revealing the influence of nanoparticle loading on flow and structural properties.
Dynamic light scattering (DLS) analysis was conducted to evaluate the polydispersity index, zeta potential, and particle size distribution, providing insights into nanoparticle dispersion and stability within the oil phase. These parameters are critical for ensuring long-term homogeneity and reliable performance under operational conditons. Additonally, the glass transition temperature (Tg) and melting temperature (Tm) of each formulation were determined to assess the thermal behavior of the nanofluids.
The combined rheological, thermal, and colloidal analysis supports the viability of TiO₂-based nanofluids as advanced insulating and heat-dissipating materials, offering promising potential for enhancing the performance and efficiency of dielectric fluids in high-voltage transformer applications.

Introduction: The mechanical properties of nanomedicines have received tremendous attention in recent years, but the mechanism by which the mechanical properties of nanomedicines affect antitumor effects is not yet clear [1-2].

Materials & Methods: We leveraged nanogels of different mechanical properties as model nanomedicines to uncover the impacts of nanomedicine mechanical properties on drug delivery and antitumor efficacy.

Results & Discussion: We found that compared with stiff nanogel, soft nanogel presented higher cellular uptake [3-4]. At the same time, nanogels with different stiffness showed significant distribution differences in varied tissues and organs. Thanks to the excellent deformability, soft nanogel can overcome tumor's dense extracellular matrix, achieve higher tumor concentration, deeper penetration and stronger antitumor effect relative to stiff counterparts. We further elucidated that the mechanical properties of blocking materials were a key parameter affecting the blocking strategy of the reticuloendothelial system. Therefore, prior injection of stiff nanogels can inhibit the clatherin-mediated endocytosis of macrophages and prolong the retention time in the liver, which can abrogate the endocytosis ability of macrophages and temporarily block the reticuloendothelial system.

Conclusions: Our study corroborates that the mechanical properties are an essential factor that profoundly affects the delivery efficiency of nanomedicines.

References

1. Li Zheng, et al. Soc. Rev. 2020, 49, 2273-2290.
2. Li Zheng, et al. Mater. 2024, 36, 1041-1053.
3. Li Zheng, et al. Nature Communications 2023, 14, 1437.
4. Li Zheng, et al. Sci. 2024, 11, 2306730.

In this study, the electronic and optical properties of a zigzag (14,0) boron nitride nanotube (BNNT) were investigated using density functional theory (DFT) with the ab initio simulation software VASP. The results revealed a characteristic density of states and an electronic band gap of approximately 0.003 eV, highlighting a semimetallic behavior for this type of nanotube. This behavior is intriguing, as BNNTs are typically known for their insulating properties, and such a discovery opens up new possibilities for applications that require semimetallic materials.

On the optical side, the calculations show several key characteristics, including absorption and the dielectric constant. Notably, significant absorption was observed in both the visible and infrared ranges, which is attributed to specific electronic interactions or unique structural modifications within the nanotube. This broad absorption spectrum suggests that BNNTs can interact effectively with a wide range of electromagnetic radiation, which is highly beneficial for optoelectronic devices.

The combination of favorable electronic and optical properties in the zigzag (14,0) BNNT suggests strong potential for use in various applications such as nanoelectronics, infrared detection devices, optical sensors, and low-dimensional electronic components. These findings pave the way for future experimental investigations to confirm the semimetallic properties of BNNTs and further optimize their performance in technological applications, especially in advanced nanodevices and sensors.

Diluted magnetic semiconductors (DMSs), also referred to as semimagnetic semiconductors, are a class of semiconductor alloys whose lattice is partially composed of substitutional magnetic atoms, such as Mn, Fe, or Co. One such effect is that charge carriers, bound to a donor impurity in DMS structures, can polarize the spins of the magnetic ions within their vicinity. This complex, which consists of a charge carrier bound to an ionized impurity and surrounded by magnetic ions with locally aligned spins, is referred to as a bound magnetic polaron (BMP). In this study, we used computational methods to analyze how the central barrier and manganese composition affect the electronic properties of a magnetic impurity confined in a double quantum well composed of a diluted magnetic semiconductor, Cd_1-xwMn_xwTe/Cd_1-xbMn_xbTe. We also employed the effective mass approximation and variational technique for numerical calculations. To compute the spin polaronic shift, we used mean field theory with the modified Brillouin function. The main findings of our work reveal that an increase in barrier thickness enhances the binding energy of the ground state of an impurity located at z_i = (L_w+L_b)/2 for all manganese compositions. Moreover, a higher composition raises the height of the barrier potential, where the effect of quantum confinement is very strong, leading to a rise in the magnetic impurity binding energy. On the other hand, the spin polaronic shift follows the same trend as the binding energy with respect to the aforementioned effects. Finally, the exchange interaction between the magnetic ion moments and the spins of conduction electrons in DMSs has paved the way for advancements in spintronic device technologies. We anticipate that this study will offer valuable insights into the electronic properties of double quantum well made from diluted magnetic semiconductors, which could prove beneficial for spintronic applications.

The green synthesis of metallic nanoparticles (MNPs) using plant-based materials offers a sustainable alternative to chemical methods and holds great promise in biomedical applications, particularly for combating antibiotic-resistant pathogens. In this study, rosemary (Rosmarinus officinalis), known for its rich phytochemical profile with antimicrobial and antioxidant properties, was used as both a reducing and stabilizing agent in nanoparticle synthesis. Rosemary extract was prepared and analyzed for its bioactive constituents using gas chromatography–mass spectrometry (GC-MS), and its antioxidant and antimicrobial activities were evaluated. The extract was then employed in the green synthesis of MNPs. The resulting nanoparticles are currently being characterized using UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and dynamic light scattering (DLS) to determine their optical, structural, and morphological properties. Preliminary results have confirmed the presence of key phytochemicals, particularly phenolic and terpenoid compounds, that facilitate metal ion reduction and nanoparticle stabilization. UV-Vis analysis indicated successful nanoparticle formation, and antimicrobial assays demonstrated promising activity against pathogenic bacterial strains. These findings highlight rosemary extract as an effective and eco-friendly agent for producing biologically active MNPs, supporting their potential as novel antibacterial agents in the fight against antibiotic resistance. This approach also not only reduces the use of hazardous chemicals but also enhances antimicrobial efficacy by combining the properties of both metal ions and plant-derived compounds.

In recent years, selenium nanoparticles have received great interest owing to their potential applications in several fields, such as medicine, optoelectronics, agriculture, and catalysis [1]. Recently, we reported the efficient biogenic synthesis of nanoparticles anchored on carboxymethylcellulose (CMC) nanocolloids [2] [3]. Herein, we present a simple and ecofriendly method for the synthesis of selenium nanoparticles (SeNPs) using selenium dioxide (SeO₂) as a precursor, L-ascorbic acid (AA) as a reducing agent, and sodium carboxymethylcellulose (CMC-Na) as a biobased surfactant. Various synthesis parameters, i.e., the pH, AA equivalence (eqv.), and CMC weight, were optimized for the synthesis of the nanocolloids CMC@SeNPs. The optimum results were obtained using a 2,4 mmol/L solution of H₂SeO₃ at pH = 8 with 3 eqv. of AA and 222 mg of CMC. The as-prepared nanocolloids were characterized using various techniques, such as UV–visible spectroscopy, FTIR spectroscopy, XRD, zeta potential measurement, and FESEM-EDX. The results showed that SeNPs were successfully synthesized with a spherical shape and crystalline structure. Moreover, the as-synthesized CMC@SeNPs were studied to determine their suitability for use as smart fertilizers for agricultural applications.

References:

[1]: A. Hussain, M. N. Lakhan, A. Hanan, I. A. Soomro, M. Ahmed, F. Bibi, I. Zehra, Materials Today Sustainability, (2023), 23, 100420.

[2]: A. A. Mekkaoui, H. Orfi, K. Bejtka, M. Laayati, S. A Labyad, L. El Firdoussi, S. El Houssame, Environmental Science and Pollution Research, (2023), 30(34), 81619-81634.

[3]: H. Orfi, A. A. Mekkaoui, B. Sündü, M. Laayati, S. A Labyad, L. El Firdoussi, S. El Houssame, J Inorg Organomet Polym Mater, (2022), 32:2192–2208.

The capacity of chitosan to form hydrogels under mild conditions and its chemical modifiability have made it widely used in drug delivery, wound healing, and tissue engineering. In recent years, particular attention has been directed toward chitosan-based nanocomposite hydrogels, which incorporate nanoparticles to enhance mechanical, biological, and functional properties. Chitosan-based nanocomposite hydrogels reinforced with nanoparticles were reviewed based on research articles retrieved from scientific databases, including PubMed, Web of Science, Scopus, ScienceDirect, Wiley Online Library, and Google Scholar.
The synthesis approaches are generally classified into ionic gelation, covalent crosslinking, and in situ nanoparticle formation. Ionic gelation relies on electrostatic interactions between the positively charged amino groups of chitosan and multivalent anions, enabling hydrogel formation without the use of toxic solvents or initiators. Covalent crosslinking methods involve the formation of stable chemical bonds between chitosan chains and crosslinkers, often leading to improved mechanical stability and long-term integrity. In situ nanoparticle formation refers to the generation of nanoparticles directly within the hydrogel matrix, allowing uniform dispersion and strong interfacial interactions with the polymer network.
Incorporated nanoparticles serve multiple roles: reinforcing the hydrogel network, enhancing antibacterial activity, or imparting specific functionalities such as magnetism or photothermal responsiveness. Critical formulation parameters greatly influence the resulting hydrogel’s mechanical strength, swelling behavior, porosity, and drug release kinetics. Additionally, blending chitosan with other natural polymers improves structural versatility and enables the design of injectable, self-healing, or stimuli-responsive nanocomposite systems.
In conclusion, the ability of chitosan-based nanocomposite hydrogels to combine bioactivity, controlled release, and structural integrity highlights their potential as next-generation materials in nanomedicine. Continued advances in synthesis methods, nanoparticle engineering, and biopolymer integration are expected to expand their clinical relevance and translational potential.

The rapid and modular assembly of hybrid nanosystems is central to the development of advanced nanomedicines, particularly for solid tumors such as neuroblastoma. While strain-promoted azide–alkyne cycloaddition (SPAAC) has emerged as a powerful tool for catalyst-free, bioorthogonal conjugation, its full potential remains constrained by the need for precise temporal control over fast-reacting systems1.
In this study, we present a custom-designed microfluidic device fabricated from polylactic acid (PLA) using affordable fused filament 3D printing technology2. The chip allows continuous-flow processing with well-defined residence times, enabling highly reproducible nanoassembly workflows. This setup was employed to drive SPAAC-mediated coupling between azide-functionalized mesoporous silica nanoparticles (MCM-41) or azide-functionalized liposomes and various DBCO-bearing entities: gold nanorods, catalase-loaded nanocapsules, and a fluorescently labeled small molecule (DBCO-Fluor 545). These components were selected to span a range of structural and chemical properties, particularly regarding differences in particle rigidity and steric impedance.
Reactions were limited to a 5-minute residence time in both the microfluidic and conventional agitation conditions. Differential centrifugation was used to isolate assembled nanostructures and remove excess reactants. The microfluidic chip consistently enabled efficient and reproducible conjugation across all systems tested, despite the rapid kinetics and low reagent concentrations typically required for biocompatible settings.
Our results demonstrate that the microfluidic system provides a robust and reproducible platform for the rapid generation of hybrid nanoassemblies. Without requiring elevated concentrations or extended reaction times, this strategy enabled the formation of covalently linked nanosystems across all tested configurations. The method offers a scalable and modular route to the fabrication of functional nanomaterials, with potential applications in drug delivery, enzyme immobilization, intracellular trafficking, and targeted cancer therapy.

Bibliography:
1.
Sletten, E. M. & Bertozzi, C. R. Bioorthogonal Chemistry: Fishing for Selectivity in a Sea of Functionality. Angewandte Chemie International Edition 48, 6974–6998 (2009).
2.
Whitesides, G. M. The origins and the future of microfluidics. Nature 442, 368–373 (2006).