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The influence of solvent polarity on the self-assembly processes and its effect on the morphological outcome of self-assembled aggregates is another domain that requires a comprehensive study. The present investigation aims to address these issues by employing a unique "V-shaped" luminogen (TBNap, N-(3-pyridyl)-4-amino-1,8-naphthalimide Tröger's base), where the two 1,8-naphthalimide units are nearly orthogonal to each other. The TBNap is synthesized in high yield and fully characterized using standard characterization methods, including X-ray diffraction analysis, which reveals distinctly different structural arrangements of TBNap crystallized as different solvates in various solvent media. Furthermore, due to its internal charge transfer nature, the TBNap exhibits positive solvatochromism and solvent-guided morphogenesis. Given the unique structure, TBNap displays aggregation-induced emission enhancement in THF-H₂O medium and forms self-assembled fluorescent nanoaggregates as imaged using different microscopic imaging techniques such as scanning electron microscopy (SEM) and confocal fluorescence microscopy. Furthermore, the latter is employed to demonstrate the in situ real-time visualization of these fluorescent nanoaggregates formations in native conditions and correlate the morphological outcome with SEM imaging.

Pathological scar treatment remains a clinical challenge, and novel efficient and safe approaches are urgently needed. Regulation of cell fate transition has promising potential for disease treatment and tissue regeneration. Skin fibrosis is linked to a specific fibroblast subtype marked by dipeptidyl peptidase IV (DPP4⁺), by which various agents, including sitagliptin, an established antidiabetic medication, can inhibit. In this study, it is hypothesized that pharmacological inhibition of DPP4 with sitagliptin could redirect fibroblasts toward adipogenic lineages, consequently, preventing scar formation. Fibroblasts from human keloid tissues are first isolated and characterized, confirming their mesenchymal stem cell (MSCs) properties and termed them as keloid-derived MSCs (KMSCs). The analyses reveal that DPP4^- KMSCs exhibit enhanced adipogenic potential, whereas DPP4⁺ KMSCs display greater fibrotic potential. In KMSCs, sitagliptin promotes adipogenesis by inhibiting DPP4-mediated IGF1 truncation, thereby enhancing IGF1 signaling. Furthermore, sitagliptin-loaded microneedle patches are developed capable of sustained, controlled release of sitagliptin or IGF1 into cutaneous wounds, effectively reducing scar formation by promoting the conversion of fibroblasts into adipocytes in vivo. Overall, the findings propose a novel application for sitagliptin in preventing scar formation via cell fate modulation during wound healing, thereby advancing clinical treatment strategies for scars.

The evolution of label-free electrochemical biosensors has revolutionized the field of analytical detection by enabling rapid, direct, and sensitive detection of a wide range of analytes. Electrochemical impedance spectroscopy (EIS) provides mechanistic insight into the interfacial changes occurring at the electrode/electrolyte interface, thereby enabling real-time monitoring. Direct detection of molecular binding events at the electrode interface is made possible by sensing measurable shifts in interfacial impedance characteristics. Despite their versatility, the commercial translation of EIS-enabled biosensors has been hindered by challenges in achieving robust sensitivity, specificity, and reproducibility. Recent progress in the field, including integration of nanoengineered electrode materials and novel biorecognition elements, has addressed some of these limitations, resulting in marked improvements in EIS-based biosensor performance. This review discusses the mechanistic principles underlying label-free EIS biosensing and highlights recent developments in electrode surface modification and sensor architecture. It also explores the integration of novel biorecognition elements and describes how their impact on sensor performance may be assessed. Current limitations and future directions for the application of EIS-enabled sensors in clinical diagnostics, environmental analysis, and food safety monitoring are also considered.

Charge trap memristors (CTM) are promising candidates for nonvolatile analog units in crossbar array platforms, offering a pathway to next-generation high-density memory and synaptic arrays, due to their low-current operation and self-rectifying characteristics. However, the charge trapping process is inherently slow, posing a significant challenge to achieving high-speed operation. In this study, a CTM device incorporating a gold nanoparticle (Au NP) layer, referred to as NP-CTM, is proposed. This design improves programming speed by a factor of ≈47.6, while maintaining excellent stability and retention characteristics. These enhancements are attributed to the synergistic effects of enhanced electric fields and an engineered band structure, both achieved through the physical structure and material properties of Au NPs. The findings are validated through multiphysics-based simulations and conduction band model analyses. The improved speed and the resulting reduction in programming energy of the CTM device make it a promising candidate for large-scale applications.

Aqueous zinc (Zn) metal batteries (AZBs) have emerged as highly promising candidates for large-scale energy storage systems because of their inherent safety and cost-effectiveness. However, their practical implementation remains constrained by parasitic side reactions and uncontrolled dendrite growth at the metallic Zn anode. Herein, a microenvironment-controlled additive strategy is proposed via employing phytic acid-functionalized montmorillonite (MPA) nanosheets as electrolyte additives for highly durable AZBs. The MPA nanosheets spontaneously assemble onto the surface of the Zn anode through interfacial self-adsorption, effectively suppressing parasitic reactions. Moreover, the regulation of interfacial chemistry enhances the zincophilic characteristic, enabling precise modulation of Zn²⁺ flux distribution and directing homogeneous Zn electrodeposition through spatially controlled ion coordination. As a result, the Zn||Zn symmetric cell with the MPA additives achieves a stable cycle for over 2800 h at 2 mA cm^-2. The assembled Zn||VO₂ full cell within the modified electrolyte maintains exceptional cycling stability of 89.5% after 1000 cycles. This work presents a facile and efficient microenvironment-regulated additive strategy for homogeneous Zn deposition, aimed at achieving highly reversible AZBs.

Laser-induced graphene (LIG) is formed by the conversion of certain carbon precursors when irradiated with a laser beam. Predesigned LIG patterns are scribed onto the precursor material in a low-cost and maskless process, which enables the fabrication of flexible and electrically conductive materials for various applications. This study explores the friction and wear behavior of LIG from a polyimide precursor. Line patterns with different widths (200, 100, 50, and 30 μm) are introduced to modify the friction properties. An ultraviolet laser source with a nominal beam size of 2 μm is used, as it allows to scribe patterns with smaller dimensions and at higher resolution compared to the more commonly applied infrared laser sources. A distinct correlation is established between the pattern and its friction behavior, where lowering the line size results in a decrease in the coefficient of friction (COF). The wear behavior is evaluated, revealing gradual wear of the protruding LIG roughness peaks and a change in the graphenic material, which reduces the COF during the running-in stage of the tribological testing. Due to its versatility in terms of precursor material, patterning options, and morphology modification, LIG represents a meaningful candidate for customized tribological applications.

Graphene-copper (Gr-Cu) composite conductors have demonstrated Gr-enhanced electrical and thermal properties. However, the conductors' coupled mechanical and electrical responses remain unexplored despite the importance of their mechanical flexibility and robustness. Here, the electromechanical behavior of a recently developed microscale Gr-Cu composite, called axially continuous graphene-copper (ACGC) wire, has been investigated by developing and utilizing a customized tensile testing method. Experimental studies have shown that 80 μm-diameter ACGC (hereafter ACGC80) wires exhibit 3.681% and 3.173% higher compared to as-received and annealed Cu wires, respectively. More importantly, the Gr-enhanced electrical performance of the ACGC80 has been observed even after significant plastic deformation under uniaxial tension. To be specific, the conductivity of ACGC80 is 3.139%, 3.144%, and 3.088% higher than that of annealed copper wire at 3, 6, and 9% strain, respectively. Analysis indicates that ACGC80 deforms by forming highly localized plastic deformation zones along its length. This result suggests that graphene in ACGC80 serves as an effective electron pathway even after applying a large strain because the pronounced damage to graphene is limited to only a small fraction of ACGC80. The ACGC80 conductor has great potential to advance emerging applications in flexible interconnects, wearable electronics, and high-power transmission for microchips.

Ti-MXene is a promising electrode material for supercapacitors. The layered structure of MXene expands due to swelling in electrolytes allowing the penetration of ions into the interlayers. A study of effects related to the match between the size of cations in hydrated or dehydrated state and the interlayer distance of MXene is performed here using operando X-ray diffraction (XRD) in capillary-size supercapacitors with alkali metal chloride electrolytes. The supercapacitors are studied during charging and discharging over several cycles revealing structural changes at both MXene electrodes. Experiments reveal an expansion of the MXene c-lattice in LiCl, NaCl, and KCl electrolytes (compared to the expansion in pure water) under an increase of applied voltage from 0 to 1 V and structural oscillations related to a change of polarity. The interlayer spacing of MXene remains close to the water-swollen state in RbCl, CsCl, and NH₄Cl electrolytes showing no further expansion as a function of applied voltage. Only rather small variations of interlayer spacing are found in H₂SO₄ electrolyte during tens of charge-discharge cycles. Analysis of the match between the sizes of ions and the width of MXene interlayers demonstrates that some cations and anions could be inserted into MXene interlayers only in dehydrated state.

Nanobiomedicine promises to revolutionize life quality and expectancy of patients with cognitive impairment and cancer malignancies, via unraveling key molecular processes related to their onset useful as biomarkers of disease to develop and improve the efficacy of therapies. However, it is still a challenge understanding and identifying these molecular mechanisms as biomarkers of disease, because of their high-level of polymorphism and nanoscale dimensions. Here, it provides a review work linking the potential and capabilities of atomic force microscopy (AFM) technologies in unraveling beyond imaging the common and hidden properties of transient and nanosized molecular processes in cancer and neurodegeneration. This study highlights the most prominent operational modes of AFM to achieve morphological, mechanical, and chemical characterization of the molecular processes leading to these diseases. Finally, it outlines the advantages of AFM compared with other techniques to guide newcomers and stakeholders toward potential future avenues opened by AFM methods in nanobiomedicine.

The minimally invasive repair of soft tissue defects remains a major clinical challenge due to the lack of biomaterials that simultaneously fulfill key requirements, including extrudability, strong adhesion, seamless integration, bioactivity, and appropriate mechanical properties. Here, a multifunctional double-network composite hydrogel is presented that is synthesized from modified hyaluronic acid (HA) and silk fibroin (SF) through a stepwise gelation process. The incorporation of ferric ions enables dynamic crosslinking of dopamine-grafted HA, resulting in the rapid formation of adhesive hydrogels with microporous structures. Sonication-induced β-sheets in SF form a secondary network, enhancing mechanical strength with reduced swelling and degradation. The inclusion of curcumin-loaded particles within the hydrogel promotes anti-inflammatory and antifibrotic activity by promoting macrophage polarization toward the reparative M2 phenotype and reducing TGF-β-induced fibroblast differentiation and collagen deposition. In situ injectability and printability of the hydrogel are demonstrated in ex vivo porcine vocal fold models. In vitro and in vivo biological evaluations in rat models confirm the cytocompatibility of the hydrogel and its ability to support cell penetration. Mechanical, structural, and biological results collectively support the applicability of this hydrogel as a minimally invasive solution for soft tissue defect repair, particularly in mechanically dynamic tissues such as the human vocal folds.