Search Results (2,748)

Dextrin-based nanosponges (D-NS) are promising candidates for oral drug delivery due to their biocompatibility, mucoadhesive properties, and tunable swelling behavior. In this study, pH-sensitive nanosponges were synthesized using β-cyclodextrin (β-CD), GluciDex^®2 (GLU2), and KLEPTOSE^® Linecaps (LC) as building blocks, crosslinked with pyromellitic dianhydride (PMDA) and citric acid (CA). The nanosponges were mechanically size-reduced via homogenization and ball milling, and characterized by FTIR, TGA, dynamic light scattering (DLS), and zeta potential measurements. Swelling kinetics, cross-linking density (determined using Flory–Rehner theory), rheological behavior, and mucoadhesion were evaluated under simulated gastric and intestinal conditions. The β-CD:PMDA 1:4 NS was selected for drug studies due to its optimal balance of structural stability, swelling capacity (~863% at pH 6.8), and highest apomorphine (APO) loading (8.23%) with 90.58% encapsulation efficiency. All nanosuspensions showed favorable polydispersity index values (0.11–0.30), homogeneous size distribution, and stable zeta potentials, confirming suspension stability. Storage at 4 °C for six months revealed no changes in physicochemical properties or apomorphine (APO) degradation, indicating protection by the nanosponge matrix. D-NS exhibited tunable swelling, pH-responsive behavior, and mucoadhesive properties, with nanoparticle–mucin interactions quantified by the rheological synergism parameter (∆G′ = 53.45, ∆G″ = −36.26 at pH 6.8). In vitro release studies demonstrated slow, sustained release of APO from D-NS in simulated intestinal fluid compared to free drug diffusion, highlighting the potential of D-NS as pH-responsive, mucoadhesive carriers with controlled drug release and defined nanoparticle–mucin interactions. Full article

The threats leading to the extinction of humanity accelerate the evolution and development of materials that are capable of providing conditions for preserving health and, implicitly, life. In our work, we developed drug delivery systems based on mesoporous silica which can deliver an antibiotic, bacitracin, in a more controlled manner. The synthesis of the FDU-12 was performed through a sol–gel method and alternatively functionalized with -NH₂ groups or with poly(N-acryloylmorpholine) chains. The loading of bacitracin was performed using the vacuum-assisted method we successfully used to load these mesoporous materials preferentially within the pores as proved by the TGA-DSC results. The release was performed in two types of simulated body fluid (SBF) and this process was evaluated with chromatographic method using UV detection. The obtained data were fitted in three mathematical models of kinetic drug release (Weibull model, Korsmeyer–Peppas model, and nonlinear regression). The antimicrobial evaluation demonstrated that bacitracin-loaded FDU-12 formulations exhibited strong activity against both reference and clinical Staphylococcus strains. At sub-inhibitory concentrations, all formulations significantly reduced microbial adherence and biofilm formation, although certain strain-dependent stimulatory effects were observed. Furthermore, exposure to sub-MIC levels modulated the production of soluble virulence factors (hemolysins, lipase, and amylase), in a formulation- and strain-dependent manner, underscoring the ability of surface-functionalized FDU-12 carriers to influence bacterial pathogenicity while enhancing antimicrobial efficacy. Full article

The shift toward sustainable packaging requires biodegradable, active alternatives. This study developed ternary nanohybrids by loading carvacrol (CV) or trans-cinnamaldehyde (tCN) onto zinc oxide/natural zeolite (ZnO/NZ) hybrids, which were incorporated into a poly-L-lactide/tri-ethyl citrate (PLA/TEC) matrix via melt extrusion to produce active films. A key finding was the distinct interaction mechanism: tCN underwent strong chemisorption with ZnO, creating a sustained-release reservoir, while CV was predominantly physisorbed, leading to rapid release. This interfacial divergence dictated functional performance. Antibacterial assessment of nanohybrids revealed that tCN@ZnO/NZ0.25 exhibited the highest inhibition zones against pathogens, correlating with its chemisorbed reservoir. In films, however, CV-based formulations (especially CV@ZnO/NZ0.25) showed superior immediate antioxidant activity (EC₅₀, ~DPPH~ = 34.43 mg/mL) and an 82% reduction in oxygen permeability. In contrast, tCN-based films (especially tCN@ZnO/NZ1.0) demonstrated superior, sustained antibacterial efficacy. In a minced pork preservation study, both films delayed lipid oxidation and preserved heme iron, while the tCN-based film provided better long-term microbial control. This work demonstrates that engineering the nanocarrier–active compound interface enables precise tailoring of release kinetics, which can be optimized for either high immediate antioxidant power or long-term antimicrobial action, depending on specific food preservation requirements. Full article

Silica spicules provide a natural transdermal conduit but require a linker that binds strongly under physiological conditions and releases payloads selectively in response to biological cues. Existing silane chemistries or polydopamine coatings lack enzyme responsiveness and show limited control over release. We created a 180-member peptide library with the motif L–X1–X2–[Y–F–Y]–A–L–G–P–H–C and screened for silica binding. Biophysical assays (circular dichroism, ζ-potential, quartz crystal microbalance, atomic force microscopy) and molecular dynamics identified high-affinity binders. The lead, P176, was tested for matrix metalloprotease (MMP)-responsive cleavage. Conjugation and release of Vitamin C and Stigmasterol were analyzed by HPLC and Franz diffusion cells. P176 showed high silica affinity (~55 µg mg⁻¹), robust biophysical signals (Δf −35 to −38 Hz; rupture force ~154 pN; ζ shift −22 to−11.5 mV), and favorable adsorption energy (−48.5 kcal mol⁻¹, contact 4.5 nm², 8.5 H-bonds). The MMP gate displayed efficient kinetics (Vmax 117.9 RFU·min⁻¹, Km 5.0 µM) with >90% cleavage at 60 min, reduced to 26% by inhibitor. Conjugation yields reached 87% (Vitamin C) and 77% (Stigmasterol). Franz diffusion showed MMP-dependent release (24 h: Vitamin C 90–96%, Stigmasterol 80–85%) with minimal basal leakage. Released Vitamin C enhanced collagen I to ~250% in fibroblasts, while Stigmasterol attenuated LPS-induced macrophage morphology; keratinocytes retained normal marker expression. This study demonstrates that a single amphipathic, sequence-programmed peptide can couple strong silica anchoring with protease-responsive release and broad payload compatibility, establishing a versatile platform for spicule-based transdermal and regenerative delivery. Full article

The application of nanotechnology in medicine has garnered significant interest, particularly in the development of advanced drug delivery systems. Graphene oxide (GO) shows promise as a carrier for delivering microRNA (miRNA) mimics or antisense constructs. miRNAs play a crucial role in regulating gene expression, and their dysregulation is associated with various diseases, including cancer. This study aimed to evaluate the impact of graphene oxide on cellular signaling pathways and its potential as a platform for gene delivery by developing a GO–antisense miRNA-21 nanosystem in HepG2 liver cancer cells. A colloidal dispersion of GO was used to prepare GO-antisense miRNA-21 nanosystems via self-assembly. The nanosystem was characterized in terms of ultrastructure, size distribution, surface composition and binding by TEM, DLS, ATR-FTIR and UV-Vis spectra. Zeta potential measurements were conducted to evaluate nanosystem stability by assessing the release kinetics of antisense miRNA-21. The efficiency of the GO nanosystem in delivering antisense miRNA-21 into HepG2 cells was analyzed using confocal microscopy and flow cytometry. Given the central role of miRNA-21 in inflammatory and oncogenic pathways, we first assessed its expression following GO exposure. In line with previous studies reporting high miRNA-21 expression in hepatocellular carcinoma cells, GO treatment further increased miRNA-21 levels in HepG2 cells compared with untreated controls. Changes in the expression levels of IL-8, MCP-1, ICAM-1, TIMP-2, and NF-kB were quantified by qPCR analysis. The ultrastructural analysis confirmed a strong affinity between GO and antisense miRNA-21. Transfection results demonstrate that the GO-based nanosystem effectively delivered antisense miRNA-21 into HepG2 cells, leading to a reduction in the expression of key pro-inflammatory genes. These findings suggest that GO-based nanocarriers may offer a promising strategy for delivering localized intratumoral miRNA-based therapies that target gene regulation in hepatocellular carcinoma. Full article

Atherosclerosis remains a leading cause of cardiovascular mortality despite advances in pharmacological and interventional therapies. Current treatment approaches face limitations including systemic side effects, inadequate local drug delivery, and restenosis following vascular interventions. Gel-based technologies offer unique advantages through tunable mechanical properties, controlled degradation kinetics, high drug-loading capacity, and potential for stimuli-responsive therapeutic release. This review examines gel platforms across multiple scales and applications in atherosclerosis research and intervention. First, gel-based in vitro models are discussed. These include hydrogel matrices simulating plaque microenvironments, three-dimensional cellular culture platforms, and microfluidic organ-on-chip devices. These devices incorporate physiological flow to investigate disease mechanisms under controlled conditions. Second, therapeutic strategies are addressed through macroscopic gels for localized treatment. These encompass natural polymer-based, synthetic polymer-based, and composite formulations. Applications include stent coatings, adventitial injections, and catheter-delivered depots. Natural polymers often possess intrinsic biological activities including anti-inflammatory and immunomodulatory properties that may contribute to therapeutic effects. Third, nano- and microgels for systemic delivery are examined. These include polymer-based nanogels with stimuli-responsive drug release responding to oxidative stress, pH changes, and enzymatic activity characteristic of atherosclerotic lesions. Inorganic–organic composite nanogels incorporating paramagnetic contrast agents enable theranostic applications by combining therapy with imaging-guided treatment monitoring. Current challenges include manufacturing consistency, mechanical stability under physiological flow, long-term safety assessment, and regulatory pathway definition. Future opportunities are discussed in multi-functional integration, artificial intelligence-guided design, personalized formulations, and biomimetic approaches. Gel technologies demonstrate substantial potential to advance atherosclerosis management through improved spatial and temporal control over therapeutic interventions. Full article

The capability of wind turbines (WTs) to provide frequency response is crucial for future power systems with high wind power penetration. Existing strategies primarily focus on mitigating initial and secondary frequency drop (SFD), often overlooking the adverse effects of rotor speed recovery on turbine safety and sustained grid support. Moreover, the lack of a dynamic linkage between the frequency support stage (FSS) and speed recovery stage (SRS) impedes multi-objective coordination encompassing initial drop suppression, SFD mitigation, and rapid rotor speed recovery. To address these gaps, this paper proposes a two-stage coordinated control strategy. In the FSS, the frequency regulation coefficients (K_p and K_d) are adaptively adjusted based on available kinetic energy, ensuring its rational release. Subsequently, the switching timing from FSS to SRS is optimized using these coefficients to suppress the SFD and accelerate recovery. Finally, a fuzzy logic-based PI controller dynamically governs the SRS to restore rotor speed efficiently while further alleviating the SFD. Simulation results confirm the effectiveness of the proposed strategy under two wind speeds. It improves the initial frequency nadir by up to 0.197 Hz over no frequency control, reduces the secondary frequency drop by as much as 0.106 Hz compared to the stepwise method, and accelerates rotor speed recovery by over 30%, quantitatively validating its superior coordinated performance. Full article

Dissolvable microneedles (DMNs) represent an innovative approach to patient-friendly drug delivery, eliminating the need for conventional hypodermic injections. This study reports on the fabrication, Confocal Laser Scanning Microscopy (CLSM)-based optical visualization of drug distribution, and mechanical characterization of maltose-based DMNs impregnated with lignocaine, a local anesthetic. Microneedles were fabricated using a micro-molding technique and dried for nine hours. Structural integrity was evaluated using Field Emission Scanning Electron Microscopy (FESEM); drug distribution was examined via CLSM; and mechanical strength was assessed using nanoindentation. The FESEM results showed uniform microneedle formation with sharp tips and smooth surfaces, averaging 435 µm in height and 116 µm in width, with no significant dimensional variability (p > 0.5). CLSM analysis indicated even distribution of lignocaine throughout the matrix. Mechanical testing showed that each microneedle withstood 0.6 N, surpassing the 0.1 N threshold required for skin insertion. These results support the viability of maltose-based DMNs for local anesthetic delivery, with implications for outpatient, pediatric, and self-administered care settings. Future investigations will include Franz diffusion and in vitro dissolution studies to examine release kinetics. Full article

High penetration of wind farms into the power grid lowers system inertia and compromises stability. This paper proposes a grid-forming control strategy for Permanent Magnet Synchronous Generator (PMSG) wind turbines based on DC-link voltage matching and virtual inertia. First, a relationship between grid frequency and DC-link voltage is established, replacing the need for a phase-locked loop. Then, DC voltage dynamics are utilized to trigger a real-time switching of the power tracking curve, releasing the rotor’s kinetic energy for inertia response. This is further coordinated with a de-loading control that maintains active power reserves through over-speeding or pitch control. Finally, the MATLAB/Simulink simulation results and RT-LAB hardware-in-the-loop experiments demonstrate the capability of the proposed control strategy to provide rapid active power support during grid disturbances. Full article

Sluggish oxygen reduction reaction (ORR) remains a critical barrier to advancing intermediate-temperature electrochemical energy devices. Here, we demonstrate that strain engineering in two platforms, epitaxial thin films and freestanding membranes, systematically tunes ORR kinetics in Ruddlesden-Popper LaSrCoO₄. In epitaxial films, film thickness is varied to control in-plane tensile strain, whereas in freestanding membranes strain relaxation during the release step using water-soluble sacrificial layers produces flat or wrinkled architectures. Electrochemical impedance spectroscopy analysis reveals more than an order of magnitude increase in the oxygen surface exchange coefficient for tensile-strained films relative to relaxed films, together with a larger oxygen vacancy concentration. Wrinkled freestanding membranes provide a further increase in oxygen surface exchange kinetics and a lower activation energy, which are attributed to increased active surface area and local strain variation. These results identify epitaxial tensile strain and controlled wrinkling as practical design parameters for optimizing ORR activity in Ruddlesden-Popper oxides. Full article

The evolution mechanism of the bearing layer in the surrounding rock of tunnels with rockburst risk is extremely complex under bolt anchorage in deep strata. In this paper, the stress response, energy evolution, and crack development under different in situ stress levels and rock bolt quantities are systematically investigated. The results found that significant stress concentration and energy accumulation zones tend to form in the surrounding rock under high in situ stress conditions. The rapid unloading of radial stress and the sudden increase in kinetic energy are well-correlated in terms of time, representing important characteristics of dynamic rock failure. A significant decrease occurs in the maximum radial stress, kinetic energy, and strain energy of the surrounding rock as the number of rock bolts increases, while the number and connectivity of cracks notably weaken. This causes the failure process of the surrounding rock to transition from unstable to controlled development. It is indicated that rock bolt support can reduce the potential risk of rockbursts by regulating stress redistribution and energy release paths under high in situ stress. The findings provide a reference for evaluating surrounding rock stability and optimizing support parameters in deep-buried tunnels. Full article

As the core technology of the new energy revolution, lithium-ion batteries have broad development prospects and significant strategic importance. With continuous improvements in energy density, enhanced safety, and breakthroughs in fast-charging technology, lithium-ion batteries will play a more substantial role in fields such as new energy vehicles and energy storage. Nevertheless, the development of the lithium-ion battery industry still faces safety issues related to thermal runaway risks. The intense exothermic reactions during thermal runaway can release flammable gases, potentially leading to uncontrolled combustion or explosions, thereby posing major safety threats. This paper reviews the analysis of gas composition and patterns during lithium-ion battery thermal runaway under different conditions, as well as research on gas explosion characteristics. It introduces advanced methods for gas detection and suppression during thermal runaway and summarizes studies on the chemical kinetic mechanisms and predictive models of gas generation during thermal runaway. These studies provide a scientific basis for improving the reliability of renewable energy storage systems and formulating and refining battery safety standards. Full article

Glycerol-(9,10-trioxolane) trioleate (OTOA) is a promising material that combines good plasticizing properties for PLA with profound antimicrobial activity, which makes it suitable for application in state-of-the-art biomedical and packaging materials with added functionality. In this study, the biodegradation kinetics of PLA + OTOA mixed films under soil conditions was assessed over 180 days. Structural and morphological changes that occurred on the surface and in the volume of the films during degradation were scrutinized using DSC, X-ray diffraction, IR, and UV spectroscopy. Morphological changes were assessed using optical and confocal microscopes. The different behavior of the PLA + OTOA blend films during decomposition in soil is explained by their structure and the rate of release of antibacterial OTOA from the PLA matrix. The decomposition rate constants were determined for all films, where k_d for PLA samples is 28 µm·year⁻¹, for samples containing 10% and 30% OTOA k_d is 2 µm·year⁻¹, and for PLA + 50% OTOA samples k_d = 34 µm·year⁻¹. This is explained by changes in the structure and degree of crystallinity of materials during the process of aging in the soil. These results clarify the biodegradation processes of biomaterials containing antibacterial agents in their structure. Full article

Smart nanocarriers are being increasingly explored to improve the performance selectivity of cancer chemotherapy. Here, two pH-responsive magnetic nanocarriers were developed using quaternary chitosan (HTCC) functionalized with 3-(triethoxysilyl)propyl isocyanate- ICPTES (MNP-HTCC1) or 3-(glycidyloxypropyl)trimethoxysilane-GPTMS (MNP-HTCC2) to form hybrid silica shells on Fe₃O₄ cores. The resulting core–shell nanoparticles (14.5 and 12.5 nm) displayed highly positive zeta potentials (+45.4 to +27.1 mV, pH 4.2–9.5), confirming successful HTCC incorporation and strong colloidal stability. Both nanocarriers achieved high doxorubicin (DOX) loading at pH 9.5, reaching 90% efficiency and a capacity of 154 µg DOX per mg. DOX release was pH-dependent, with faster release under acidic conditions relevant to tumor and endo-lysosomal environments. At pH 4.2, MNP-HTCC1 released 90% of DOX over 72 h, while MNP-HTCC2 released 79%. Release at pH 5.0 was intermediate (67–72%), and moderate at physiological pH (43–55%). All formulations showed an initial burst followed by sustained release. Kinetic modelling (Weibull) indicated a diffusion-controlled mechanism consistent with Fickian transport through the HTCC–silica matrix. Cytotoxicity assays using MCF-7 breast cancer cells revealed greater cytotoxicity for DOX-loaded nanocarriers compared with free DOX, with MNP-HTCC1 showing the strongest effect. Overall, these HTCC-based magnetic nanocarriers offer efficient loading, controlled pH-triggered DOX release, and enhanced therapeutic performance. Full article

Background/Objectives: Mathematical modelling provides a quantitative way to describe the fate and action of drugs in the oral cavity, where transport processes are shaped by salivary flow, pellicle formation, biofilm structure and the wash-out effect of gingival crevicular fluid (GCF). Local pharmacokinetics in the mouth differ substantially from systemic models, and therefore a dedicated framework is required. The aim of this work was to present a structured, physiologically based concept that links in vitro release testing with local pharmacokinetics and pharmacodynamics. Methods: A narrative review with elements of systematic search was conducted in PubMed, Scopus and Web of Science (1980–2025) for publications describing drug release, local PBPK, and PK/PD modelling in the oral cavity. Mathematical formulations were grouped into release kinetics, mini-PBPK transport and local PK/PD relations. Classical models (Higuchi, Korsmeyer–Peppas, Peppas–Sahlin) were integrated with a mini-PBPK structure describing saliva–mucosa–biofilm–pocket interactions. Results: The combined model captures adsorption to pellicle, diffusion within biofilm and wash-out by GCF. It allows simulation of variable clinical conditions, such as inflammation-related changes in Q_GCF, and links local exposure to pharmacodynamic outcomes. Case studies with PerioChip^®, Arestin^®, and Atridox^® demonstrate how mechanistic models explain observed therapeutic duration and low-systemic exposure. Conclusions: The proposed mini-PBPK framework bridges empirical release data and physiological transport in the oral cavity. It supports rational formulation design, optimisation of local dosage, and personalised prediction of drug retention in gingival pockets. This modelling approach can become a practical tool for the development of dental biomaterials and subgingival therapies. Full article