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Polyethylene terephthalate micro- and nanoplastics (PET-NPs) constitute a prevalent and enduring environmental risk, yet detailed mechanistic kinetics of their breakdown in environment remain poorly studied. This work presents robust multi-scale computational methodology which extends a semi-empirical computational procedure for predicting multistep chemical reaction kinetics for polymers, specifically focusing on PET nanoparticles degradation under neutral, acidic, and alkaline conditions. Our approach combines Density Functional Theory calculations with an adapted Shrinking Core Model to predict degradation rates, eliminating the reliance on empirically adjusted rate constants. Model accuracy was confirmed by strong agreement with experimental PET degradation data. Our findings reveal a striking difference in degradation rates: alkaline conditions significantly accelerate the hydrolysis of PET, decomposing it within hundreds of hours to days, while acidic conditions, cause extremely slow degradation, taking decades. Crucially, our model quantifies that increased BET surface area and porosity of PET nanoparticles are primary drivers of degradation efficiency. The multiscale platform serves as a reliable, predictive nanoengineering tool model for evaluating that describes PET longevity in aquatic systems and supports advanced strategies for the safe and sustainable development of synthetic polymers and for improved plastic waste management.

Metallic nanoparticles (MNPs) have attracted significant interest among researchers since the previous century owing to their vast potential applications in emerging fields such as nanotechnology, nano-optics, nanoengineering, nanoenergy, and biomedicine. The rapidly increasing demand for various MNPs has driven researchers to develop facile, inexpensive, scalable, and sustainable synthesis methods to explore their properties and potential for future applications across different scientific and industrial sectors. Due to their intrinsic physicochemical properties, such as surface plasmon resonance, biocompatibility, and luminescence behavior, MNPs have found numerous biomedical applications. Currently, these materials are synthesized and functionalized with different chemical groups, allowing them to conjugate with ligands, antibodies, and drugs of interest. This enables a wide range of applications in biotechnology, targeted drug delivery, magnetic separation, gene and drug delivery vehicles, and importantly, the diagnosis, imaging, and treatment of cancers. Key factors such as size-dependent melting temperature, surface plasmon resonance-based luminescence, and biocompatibility make MNPs highly valuable in bio-industrial applications. Various imaging modalities such as CT, MRI, SERS, ultrasound (US), and other optical imaging techniques have been developed to aid in disease detection and monitoring at various stages. The development of new biomedical techniques and applications requires a comprehensive understanding of the interactions between MNPs and target cells. This review focuses on different types of metallic nanoparticles, their advanced synthesis strategies such as biogenic approaches in addition to conventional methods, and their up-to-date biomedical applications including early detection, diagnosis, imaging, efficient drug delivery, and cancer therapy. Moreover, their antimicrobial activities against harmful bacteria, viruses, and fungi are discussed in detail. In addition, these nanoparticles are highlighted as optical contrast agents for bioimaging techniques such as SERS, MRI, and computed tomography, as well as for use in biosensors to detect biological molecules. Furthermore, by taking advantages of intriguing properties of various metals, biogenically synthesized bimetallic, mixed metal oxides, bifunctional composites, and graphene-based metal composites, can enhance the performance and need to be explored in future for advanced bio medicinal applications.

The therapeutic efficacy of osteoporosis (OP) treatments is often limited by inadequate cellular precision and poor accumulation within the bone microenvironment. Although synthetic nanoparticles have been developed to address these challenges, they commonly face biological barriers such as rapid systemic clearance, inefficient transendothelial transport, and limited affinity for the complex bone niche. Here, we report on a biomimetic nanobiotechnology platform that integrates biological recognition with precision polymer engineering to overcome these limitations. We engineered a core-shell nanostructure consisting of a bilirubin-loaded Poly D L-Lactide-co-glycolide (PLGA) core cloaked with genetically modified osteoblast (OB)-derived membranes overexpressing the Ephrin type-B receptor 4 (EphB4) receptor. This biomimetic nanoparticle (NP) exploits the endogenous EphB4-EphrinB2 (EFNB2) signaling axis to achieve selective recognition and preferential uptake by EFNB2-expressing osteoclasts (OCs), displaying significantly higher internalization in OCs compared with mesenchymal stem cells (MSC), macrophages (Mφ), and OBs in vitro. Furthermore, the cell-membrane corona enables efficient transendothelial migration under inflammatory conditions, facilitating targeted delivery to OCs beyond the vascular endothelium. In vitro molecular analyses demonstrated that receptor-mediated NP uptake significantly suppressed key osteoclastogenic regulators, including nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), cathepsin K, and matrix metalloproteinase-9 (MMP-9). In a preclinical OP model, systemic administration resulted in bone-specific accumulation and robust restoration of trabecular microarchitecture and bone mineral density (BMD). Collectively, this work demonstrates that interfacial nanoengineering can translate complex receptor-guided biological interactions into stable, high-performance nanotherapeutics for the precision treatment of skeletal disorders.

In this work, we have nanoengineered clean and nontoxic Cu@Cu2O core-shell nanoparticles by the pulsed-laser-ablation technique and systematically evaluated their antibacterial efficacy, biocompatibility, and surface-enhanced Raman scattering (SERS) performance. The structural, optical, morphological, and elemental characterization studies were conducted using X-ray diffraction, UV-vis absorption spectroscopy, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy. The TEM confirms the formation of Cu@Cu2O core-shell nanoparticles with an average particle size of 5.6 nm. The quantitative assessment of antibacterial efficacy, namely, two-way ANOVA followed by post-hoc test and analysis, reveals concentration-dependent activity of the nanocomposites against both Escherichia coli and Bacillus pumilus and indicates that inhibition of bacterial growth was strong even at a concentration as low as 5 μg mL-1. On the other hand, cell viability assays with a comprehensive 48 hour temporal study, suggest that the nanoparticles are biocompatible with human embryonic kidney (HEK-293) cells and safe for clinical applications with an appropriate dose. Furthermore, we also present SERS activity of Congo red dye molecules using the laser-synthesized Cu@Cu2O core-shell nanoparticle substrate, for the first time, improving the limit of detection by three orders of magnitude down to a concentration of 10-8 M. These results establish the Cu@Cu2O core-shell nanoparticles as ideal medicinal candidates with combined antibacterial efficacy, good cellular biocompatibility, and excellent SERS activity, which are beneficial for their applications in therapeutics, sensing, and environmental monitoring.

Van der Waals (vdW) materials have emerged as a promising platform for next-generation nanophotonics and optoelectronics. However, employing vdW materials as a core photonic integration platform, rather than as passive or active overlays on conventional silicon-based platforms, remains challenging, leaving their full potential untapped. Here we develop a nanofabrication strategy that enables high-resolution patterning across a broad range of vdW materials, including insulators, semiconductors, ferroelectrics and their heterostructures, and we show that they can be used as the intrinsic platform for low-loss microcavity nonlinear photonic devices such as microdisks, photonic crystals and metasurfaces. We demonstrate vdW microdisk resonators with quality (Q) factors exceeding 106. Such Q factors enable efficient continuous-wave nonlinear optical processes, including second-harmonic generation, sum-frequency generation and optical parametric amplification, with full free-spectral-range thermal tunability. These results position vdW materials as key material building blocks for next-generation integrated photonics and optoelectronics.

Time-resolved luminescence enables high sensitivity measurements and determination of radiative lifetimes for a number of applications. The combination of time-resolved luminescence with droplet microfluidic systems creates a powerful combination of high sensitivity detection and multiplexing capabilities with high throughput sampling. This study introduces a platform for time resolved luminescence detection from a millisecond lifetime dye, CoraFluor-1-PFP (CRF-1), in microfluidic systems to further increase multiplexing applications. Optimized excitation and emission parameters was a 50 Hz (60% duty cycle) excitation cycle using a 340 nm LED combined with an 8 ms emission window. Using these parameters, the lifetime of CRF-1 was found to be 2.9 ms. These parameters were applied to a droplet microfluidic system where aqueous CRF-1 was dispersed into a fluorinated oil carrier phase. Droplet frequencies of 0.15, 0.85, and 1.85 Hz were evaluated by summation of the photon counts from each LED excitation cycle, revealing the droplet dynamics. Using this excitation and emission scheme, droplet rise times as short as 60 ms could be determined, indicating that even more rapid droplet frequencies are feasible. This platform advances time resolved luminescence assays toward automated and high-throughput analysis.

Widespread discharge of oily wastewater from industrial processes, combined with accidental oil spills, poses a significant challenge to the environment and human health. Hence, the efficient separation of oil/water mixtures is a pressing issue for sustainable development. Hydrophobic/oleophilic materials based on cellulose fibers modified with silanes show increasing interest for the selective separation of oil and water, but it remains difficult to achieve simple processing while ensuring stability, durability, environmental friendliness, and low cost. Here, a hydrophobic membrane was produced via a simple one-step modification by immersing the paper substrate (UNPr) in hydrolyzed 3-aminopropyltriethoxysilane (APTES). Heat treatment at 120 °C promoted interfacial interactions between the NH2-NH2 and NH2-OH groups via conformational rearrangements that oriented the -NH2 groups toward the fiber surfaces (inward), resulting in a transition from hydrophilic to hydrophobic surfaces. This modified paper showed a water contact angle (WCA) of over 134° and oil spread immediately with an oil contact angle (OCA) of ∼0°; moreover, the average pore volume of the membrane was 246.75 ± 469.3 μm3, which improved its selectivity and enabled efficient separation of even small water droplets.

Graphene incorporation into polymer fibers offers a strategy to tune nanoscale morphology while preserving mechanical conformity for flexible composite applications. Graphene-based dopants can enable modulation of polymer fiber structure; however, the relationship between graphene incorporation, fiber morphology, and mechanical flexibility must be evaluated. This study investigates the integration of graphene oxide (GO) and reduced graphene oxide (RGO) into fibrous materials to tailor the structural and surface characteristics by fabricating GO- and RGO-enhanced poly(vinylidene fluoride) (PVDF) fibers via a wet-spinning process and examining the tunability of their morphology and its influence on mechanical properties. The effect of graphene doping and reduction state on fiber architecture is explored using scanning electron microscopy (SEM), atomic force microscopy (AFM), and Brunauer-Emmett-Teller (BET) surface area analysis. Fourier transform infrared (FTIR) and Raman spectroscopy analyses confirmed the incorporation and reduction of graphene derivatives within the PVDF matrix while revealing corresponding changes in chemical functionality and the piezoelectric phase of PVDF. Mechanical flexibility is assessed through tensile testing, revealing increased stiffness with graphene addition, although maintaining sufficient structural integrity for wearable applications. These results collectively demonstrate that graphene doping provides a facile route to engineer composite fibers, enabling a balance between morphological complexity and mechanical compliancy, while establishing graphene-enhanced fibers as promising materials for flexible sensing systems and wearable smart textiles.

Introducing structural and/or chemical heterogeneity into otherwise ordered crystals can dramatically alter material properties. Lead-based relaxor ferroelectrics such as 0.68Pb(Mg1/3Nb2/3)O3-0.32PbTiO3 are prototypical examples. We performed three-dimensional (3D) volumetric characterization using multislice electron ptychography (MEP) and bond valence molecular dynamics (BVMD) simulations. Real-space comparisons between the two under varying strain states revealed a coherent 3D view of the "polar slush." Dipolar correlations from the atomic to domain scales are shown to be jointly modulated by strain and chemical configurations, with the best agreement found in a model accounting for both overall chemical disorder and residual short-range order. Together, MEP and BVMD provide a framework for linking atomic-scale heterogeneity in complex materials by means of complementary 3D imaging and predictive modeling.

Enhancing pyroelectric performance is essential for advancing thermal sensing and energy-harvesting applications. This study presents an effective strategy to achieve highly enhanced pyroelectricity in a flexible polyvinylidene fluoride/mica bimorph. Unlike conventional approaches that focus on domain-phase engineering to enhance intrinsic pyroelectric contribution, we engineer a more dominant role for the secondary pyroelectric contribution by a stress-induced shape change that couples to a change in the polarization via the piezoelectric effect. This mechanism is enabled by the favorable combination of a large thermal-expansion mismatch between the polymer (polyvinylidene fluoride) and the ceramic (mica), together with the inherent mechanical compliance of mica's flexibility, which allows interfacial thermal stresses to efficiently generate piezoelectricity. By combining experimental characterization with finite element modeling of the heterostructure's temperature-dependent curvature, interfacial thermal stress is identified as the dominant contributor to the large effects. Direct pyroelectric measurements reveal a highly enhanced pyroelectric coefficient ≈ -359 µC/m2K, more than an order of magnitude greater than that of single-layer polyvinylidene fluoride, highlighting its potential for applications in flexible electronics, thermal sensors, and energy harvesting systems.

Intracellular calcium release (ICR) is of fundamental importance for numerous physiological and pathological processes, from cell differentiation to neurotransmitter release and muscle contraction. The ability to precisely control ICR is crucial for understanding cellular signaling mechanisms and developing therapeutic interventions for calcium-related disorders. Light-induced ICR offers numerous advantages over conventional approaches, including superior specificity, precise spatiotemporal control, excellent reproducibility, and minimal invasiveness. Here, we demonstrate that cyanine dyes function as molecular jackhammers (MJHs) to induce ICR in human embryonic kidney (HEK) 293 and immortalized mouse myoblast C2C12 cells through vibronic-driven action (VDA) following red light (640 nm) activation. VDA generates longitudinally and axially coordinated whole-molecule vibrations, enabling mechanical interactions with cells. Structure-activity relationship studies of twenty synthesized MJHs demonstrated that sulfonate-containing derivatives most effectively triggered intracellular calcium release while exhibiting minimal cytotoxicity. Mechanistic studies showed that MJH-induced calcium release operates through the inositol-triphosphate (IP3) pathway rather than reactive oxygen species generation. Finally, we demonstrated light-activated MJH-induced calcium waves in vivo using transgenic Hydra vulgaris expressing a fluorescent calcium indicator. This work establishes MJHs as molecular-scale devices for remote control of cellular signaling, expanding the utility of cyanine dyes for modulating physiological processes with potential therapeutic applications.

Achieving ultra-high dielectric tunability with robust temperature and frequency stability poses a key challenge for next-generation microwave electronics and telecommunications devices. Likewise, the integration of such materials with silicon is critical for scalability, yet it remains a complex task. This work addresses these challenges by engineering high-quality, lead-free Ba1- xSrxTiO3 (BST; x = 0.2-0.8) epitaxial thin films. Through systematic control of composition and epitaxial strain, we have experimentally revealed the coexistence of cubic, tetragonal, rhombohedral, and orthorhombic phases, forming a mixed-phase state analogous to a morphotropic phase boundary (MPB). This phase coexistence results in exceptional dielectric properties, including ultra-high tunability (∼91%) and a high breakdown electric field (∼800 kV/cm) at room temperature (10 kHz). The films exhibit good thermal (from 330 to 473 K) and frequency (10 kHz-1 MHz) stability. The robust dielectric tunability being associated with a diffuse-phase transition at higher strontium concentrations, arising from dipole dispersion, leading to relaxor-like behavior. Theoretical studies using effective-Hamiltonian approaches confirm the emergence of the MPB-like state and its role in enhanced dielectric permittivity and tunability. Finally, integration of these BST thin films onto silicon is demonstrated, highlighting the potential for scalability. These findings bridge the gap between material innovation and industrial implementation.

Real-time force feedback is essential in many surgical specialties. While previous research has focused on force measured at the tool-tissue interface, little work has explored the benefits, limitations, or opportunities of measuring force at the surgeon-tool interface. This study aims to explore scenarios in which surgeons from different medical specialties and experience levels could benefit from receiving feedback on the force exerted at the surgeon-tool (or surgeon-tissue) interface. Exploratory qualitative research was conducted through interviews with medical practitioners (N=15). This study explored perceptions of a conceptual novel force-sensing surgical glove that could provide real-time feedback in terms of usability, utility, value, and limitations. Opportunities and barriers to implement a sensor of this type in clinical practice were also explored. Participants had experience in anesthetics, dental surgery, plastic and dermatological surgery, general surgery, and obstetrics and gynecology, as these surgical fields all require precise feedback on exerted forces. Participants identified two key areas where a force sensor could yield significant benefits: (1) it could enhance surgical training through objective skill assessment and quantifiable feedback, and (2) it could provide valuable insights into the forces applied during practice, particularly in scenarios where other sensory feedback is masked. Participants appreciated that a sensorized glove that can provide real-time force sensing at the surgeon-tool interface would allow for continued feedback irrespective of the instrument, and integrate seamlessly into their current surgical workflow. Furthermore, as surgeons in some specialisms, for example, dental or obstetrics and gynecology, perform manual tasks, having a sensorized glove would provide feedback in instances where they are physically manipulating tissue. However, participants expressed concerns about accurately defining safe force ranges due to the variability in patients' anatomical structures and the potential interference with tactile sensation. Surgeons from various clinical practices agreed that force sensing at the surgeon-tool interface could be valuable and provide them with optimal versatility as to when they would adopt force sensing. A sensorized glove could improve decision-making and surgical outcomes when other sources of information guiding force exertion are masked. Conversely, it could be detrimental when the organic information to guide force exertion is distorted when using the sensor. While the choice between interaction modalities is dependent on the accessibility of different senses during surgery, design suggestions as to where sensors are best placed on a sensorized glove are dependent on the instrument used or the type of manual procedure conducted.

The surface sensitivity and probe depth in the X-ray regime of diamond for second harmonic generation (SHG) was investigated both analytically and computationally with velocity gauge real-time time-dependent density functional theory (VG-RT-TDDFT), which includes a full multipole expansion. This was accomplished using two different approaches, by changing the number and location of layers that can generate SHG computationally and by exploiting the symmetry of a crystal, a similar pattern emerged. We find that by 1000 eV, well above the 285 eV of the C K-edge, the SHG of diamond is dominated by the bulk, quadrupole response, in agreement with our analytic calculations. The bulk response continues to grow as the energy is increased, becoming overwhelming by 7000 eV. Near the C K-edge the measurement is quite surface sensitive, however, this surface sensitivity reduces as the energy increases such that by 1000 eV (and certainly by 3500 eV) SHG is largely bulk sensitive. Moreover, we find that the specific details of the crystal orientation (i.e., comparing a (001)-terminated and (111)-terminated surface) appear to have significant effects on the surface sensitivity.

Critically sized bone defects are difficult to treat, necessitating tissue engineering strategies to restore form and function. However, translation of these approaches is often constrained by preclinical models that fail to replicate systemic comorbidities commonly seen in clinical practice, such as diabetes, prior irradiation, osteonecrosis, and osteoporosis, and instead favor healthy wound environments that may overestimate efficacy. This comprehensive review aimed to provide a detailed overview of in vivo bone regeneration strategies for critically sized defects specifically within compromised healing environments, summarizing how animal models are developed and how biomaterial, cellular, and drug delivery platforms are tailored to these disease states. Recent work has sought to address key pathological barriers including chronic inflammation, oxidative stress, poor vascularization, hypocellularity, and the limited efficacy of cell-seeding approaches through a range of bioengineered solutions. Strategies include nanoengineered drug delivery systems, bioactive ion-releasing scaffolds, immunomodulatory and antioxidant biomaterials, advanced cell provisioning, and extracellular vesicle-based therapies designed to restore redox balance, promote angiogenesis, and reestablish osteogenesis. Remaining challenges include heterogeneity and poor standardization of defect models, underrepresentation of multimorbidity and treatment-related injury, ethical and logistical barriers to large animal studies, and uncertainty in how best to bridge emerging platforms with regulatory expectations. Future directions will require coordinated refinement of disease-relevant models and development of multifunctional, context-responsive constructs to more reliably predict and improve clinical translation of bone tissue engineering therapies.

Chronic diabetic wounds are characterized by persistent inflammation, defective resolution and impaired tissue regeneration, in which macrophage dysfunction and mitochondrial damage play central roles. Here, we developed a macrophage-targeted engineered mitochondrial transplantation system by coating adipose-derived stem cell (ADSC) mitochondria with triphenylphosphonium-modified konjac glucomannan (Mito-TPP-KGM). This design preserves mitochondrial membrane potential and ATP production while reducing ROS generation, and provides a mannose-rich corona for lectin receptor-related uptake. In RAW264.7 macrophages exposed to high glucose plus H2O2 or LPS, Mito-TPP-KGM is efficiently internalized, restores mitochondrial homeostasis, rebalances glycolysis and oxidative phosphorylation, and shifts inflammatory profiles toward a less inflammatory and more reparative phenotype. Engineered mitochondria also restore efferocytosis of apoptotic neutrophil-like cells and enhance the pro-angiogenic capacity of macrophage-conditioned media, thereby improving endothelial tube formation, migration and proliferation. Blocking experiments with mannan and anti-CD206/anti-DC-SIGN antibodies, together with species-specific mtDNA quantification, indicate that mannose-type lectin receptors contribute to the uptake and immunomodulatory effects of Mito-TPP-KGM. In a db/db mouse full-thickness wound model, local delivery of Mito-TPP-KGM promotes wound repair, improves histological healing, reduces oxidative damage, enhances angiogenesis, and modulates wound macrophage phenotype, leading to accelerated wound closure; these therapeutic benefits are partially attenuated by local CD206 blockade. Collectively, these findings demonstrate that polysaccharide-engineered mitochondria can reprogram diabetic wound macrophages via targeted mitochondrial transplantation, offering a promising immunometabolic strategy for chronic wound therapy.