Journal of Materials Chemistry B最新文献

Demand for new and effective chemotherapeutic agents continues to drive the search for innovative metal-based drug candidates. We introduce here a metal–organic triangle complex as a novel candidate against breast cancer cells. The self-assembly of a new thiosemicarbazone building block, N⁴-cyclohexyl-2-(2-hydroxy-3,5-diiodobenzylidene)hydrazinecarbothioamide (H₂L), with zinc(II) ions resulted in the formation of a novel metallosupramolecular complex, [Zn₃(µ-L)₃·3DMF] (1), where DMF acts as an ancillary ligand stabilizing the coordination environment. The unique structure of the trinuclear complex, resulting from a rare ONNS bridging coordination, reveals one distorted square pyramidal and two distorted trigonal bipyramidal coordination geometries around the Zn(II) centers. Antibacterial activity of the ligand and its metal complex, assessed initially using agar well diffusion and MIC methods, reveals enhanced efficacy of the triangular complex 1. SEM analysis reveals a bacterial membrane damage mechanism underlying the antibacterial effect, which is consistent with a quantitative protein leakage study. The interactions of H₂L and complex 1 with calf thymus DNA were also found to be very strong, with binding constants of 3.1 × 10⁵ M⁻¹ and 4.9 × 10⁵ M⁻¹, respectively. Further, the in vitro cytotoxicity of the ligand and the complex was evaluated against the MCF-7 breast cancer cell line using the MTT assay. Interestingly, complex 1 showed notable inhibition of MCF-7 cell proliferation, with a promising IC₅₀ value of 10.6 µM, outperforming the standard cisplatin (36.66 µM). Further studies suggest that complex 1 is cytotoxic in nature and induces cell death in cancer cell lines by apoptosis, which was further explored via reactive oxygen species (ROS) generation assay. Integrated molecular docking and MD simulations reveal that complex 1 can engage the protein active site through strong and persistent interactions, maintaining conformational stability, which provides theoretical support for its potential anticancer activity.

Chronic non-healing wounds arise from sustained oxidative stress due to excessive reactive oxygen species (ROS) accumulation, coupled with persistent bacterial colonization. However, existing wound dressings exhibit limited capability to concurrently mitigate oxidative stress and exert antibacterial activity, thereby impeding wound repair in the adverse wound microenvironment. Herein, we designed a multifunctional hydrogel dressing by integrating biomass-derived carbon dots (CD) into a polyvinyl alcohol (PVA), gelatin, and dopamine-based polymeric gel matrix (CD@PG-PD), thereby endowing it with inherent antibacterial and antioxidant properties. The multifunctional CD@PG-PD hydrogel exhibited high mechanical strength, elevated swelling properties, and self-healing behaviour, along with pH-dependent degradation. The CD@PG-PD hydrogel exhibited pronounced antibacterial activity against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacteria, which are the primary causes of the majority of wound infections. The CD@PG-PD hydrogel lowered bacterial survival rates to 5% and 8% for E. coli and S. aureus, respectively. Moreover, CD@PG-PD demonstrated excellent biocompatibility while significantly enhancing cell migration to the scratch area, almost closing the gap. More importantly, the CD@PG-PD hydrogel successfully closed 92% of the wound area in the in vivo S. aureus-infected skin wound model, while exhibiting great hemostatic performance. As a result, this integrated strategy has significant potential for improving the healing of chronic wounds.

Breast cancer continues to be the primary malignancy impacting women globally. Traditional therapies are frequently limited by non-specific distribution of drugs, systemic toxic effects, and resistance to multiple drugs. Biomimetic nanotechnology offers a promising solution to overcome these barriers by enhancing tumor accumulation and therapeutic efficiency. Herein, we develop a biomimetic nanoparticle delivery system with bovine serum albumin (BSA) serving as a carrier molecule to co-load the photosensitizer indocyanine green (ICG) and the oxygen-carrying material perfluorohexane (PFH). The nanoparticles are camouflaged with a hybrid membrane obtained from 4T1 tumor cells and erythrocytes. The results demonstrated that this hybrid coating conferred these nanoparticles with prolonged circulation and homologous targeting capabilities, dramatically boosting accumulation at tumor sites. Moreover, PFH efficiently mitigates the hypoxic microenvironment of malignant tumors. Under 808 nm laser illumination, the synergistic photothermal and enhanced photodynamic therapy mediated by nanoparticles effectively ablated tumor tissues and exerted robust antitumor efficacy, prolonging the survival time of tumor-bearing mice. This study thus provides a hybrid membrane-based biomimetic nanoplatform for efficient therapy against hypoxic tumors.

The dynamic microenvironment of refractory wounds comprises a complex pathological system characterized by interconnected factors, such as persistent infection, chronic inflammation, and impaired tissue repair. These pathological cues substantially hinder the healing process and negatively impact patients' quality of life. Stem cell-derived nanovesicles (SC-NVs) offer a variety of reparative functions, including antimicrobial activity, immunomodulation, angiogenesis, enhanced cellular proliferation and migration, and scarless healing, thereby demonstrating substantial potential for tissue regeneration. However, topical administration of nanovesicles is limited by poor tissue retention and rapid clearance, which constrain therapeutic efficacy and necessitate repeated dosing. Hydrogels, by virtue of their excellent biocompatibility, high water content, and tunable physicochemical properties, represent promising drug delivery vehicles. This review systematically examines the microenvironmental features of refractory wounds and the therapeutic mechanisms of SC-NVs in counteracting them to promote healing. Notably, nanovesicles can be loaded by smart hydrogel systems to respond to wound microenvironmental cues and allow for on-demand release via dynamic bond cleavage or structural transformation, thereby augmenting therapeutic precision. Finally, we discuss key challenges in the clinical translation of these integrated platforms and outline their future applications in precision diagnostics and therapeutics for refractory wounds.

Hydrophobic prodrug-based microcrystalline suspensions are widely employed in long-acting injectable formulations owing to their high drug loading, minimal excipient requirements, and sustained release profiles. However, the extent to which the molecular structure—particularly linker chemistry—governs prodrug crystallization remains poorly understood. Here, we address this question by comparing two dexamethasone prodrugs with identical hydrophobic chains but distinct linkages: palmityl ketal dexamethasone (PKD) and palmityl ester dexamethasone (DXP). Using an antisolvent assembly approach in combination with multimodal characterization, we show that PKD readily forms well-defined microcrystals, whereas DXP predominantly yields amorphous aggregates. Structural analyses reveal that the ketal linker in PKD, featuring gem-dimethyl substitution, imposes conformational constraints and promotes persistent intermolecular hydrogen bonding, thereby enabling the formation of extended, ordered networks during assembly. In contrast, the hydrogen-bonding motif observed for DXP at the single-crystal level depends on specific geometries that are not readily preserved during assembly, resulting in disordered packing and amorphization. These findings identify linker geometry and conformational rigidity as key determinants of crystallization behavior and provide molecular-level design principles for long-acting injectable microcrystalline prodrug formulations.

Bacterial sepsis is a critical and life-threatening condition resulting from a dysregulated host immune response to infection and remains one of the foremost causes of mortality worldwide. In this study, a biomimetic hybrid lipid–polymer nanocarrier (VCM-LIN-P2O NPs) was designed to target the ADAM10 and TLR2 receptor pathways through integrating linoleic acid (LIN) and poly(2-ethyl-2-oxazoline) (P2O). This engineered nanoplatform attenuates excessive inflammation via concurrent binding to ADAM10 and TLR2 while ensuring targeted delivery of vancomycin (VCM) to infection sites. The potential of LIN to competitively bind to ADAM10 and TLR2 was initially examined through molecular docking and subsequently validated using microscale thermophoresis (MST), confirming the potential ability of LIN to downregulate the inflammation associated with ADAM10 and TLR2 activation. The optimized VCM-LIN-P2O NPs displayed desirable physicochemical characteristics, excellent biocompatibility, and high stability, along with a sustained drug release profile extending up to 48 hours. Furthermore, the nanocarrier exhibited enhanced in vitro antibacterial performance compared to bare VCM, along with significant antioxidant and anti-inflammatory activity, in LPS-stimulated macrophages. In a murine MRSA-induced sepsis model, treatment with VCM-LIN-P2O NPs resulted in marked bacterial clearance from major organs and the bloodstream, accompanied by a significant reduction in TNF-α, IL-1β, and IL-18 levels, thereby alleviating organ damage. Therefore, these findings establish VCM-LIN-P2O NPs as a promising multifunctional nanoplatform for targeted antibiotic delivery and effective sepsis therapy.

Correction for ‘Electrospun polymeric scaffolds enable 3D tissue-like functionality and efficient photoinduced contraction’ by Giulia Simoncini et al., J. Mater. Chem. B, 2026, 14, 2832–2842, https://doi.org/10.1039/D5TB02640G.

Hydrogel dressings have been demonstrated to be an effective strategy for promoting wound healing. However, most existing dressings remain confined to passive treatments focused on adhesion, antibacterial activity, and hemostasis, and they lack operability and the active sensing capabilities required for precise intervention. In this study, a multifunctional GCTC hydrogel was constructed using gelatin (Gel), carboxymethyl chitosan (CMCS), tannic acid (TA), and calcium chloride (CaCl₂). This system exhibiting antibacterial and antioxidant properties can be conveniently applied to irregular wounds via spraying, achieving rapid hemostasis while tightly adhering to the wound surface. Furthermore, single-walled carbon nanotubes and poly(3,4-ethylenedioxythiophene)–polystyrene sulfonate (PEDOT:PSS) were incorporated to fabricate an electrochemical sensor capable of in situ monitoring of local IL-1β levels (detection range: 0.41 pg mL⁻¹ to 1000 pg mL⁻¹), which essentially meets the requirements for inflammation assessment and provides critical guidance for timely intervention. In addition, the GCTC hydrogel effectively suppresses inflammatory responses, promotes collagen deposition and epithelial regeneration, and significantly accelerates the healing of full-thickness skin defects. This research offers a new avenue for developing wound treatment platforms capable of real-time monitoring.

Lymphatic transport is strongly influenced by the hydrodynamic size of delivered agents, yet comparisons across distinct material platforms remain limited. This work investigates this principle using a selection of Gd-based MRI contrast agents that span a wide size range and key material platforms: a small molecule Gd–DTPA, a macromolecular polymer PAA–Gd, and a nanocrystal NaGdF₄@PEG. The results reveal a clear size-dominated delivery rule: agents with hydrodynamic diameters below 10 nm efficiently enter lymphatic vessels for nodal accumulation, whereas larger nanoparticles (>20 nm) are largely excluded from lymphatic vessels and instead rely on interstitial transport. This distinct pharmacokinetic behavior was visualized through dynamic contrast-enhanced (DCE) MRI and T₁-weighted imaging (T₁WI) and validated by chlorophosphonazo III (CPN III) staining. Furthermore, subcutaneous tumor models were employed to probe the interplay between lymphatic transport and tumor microenvironments. This work moves the field forward by providing a framework to guide the design of lymphatic delivery drugs, turning material-specific observations into universal, size-informed design principles applicable across diverse platforms.

Engineering synergistic metal centres inside metal–organic frameworks (MOFs) provides an effective approach to simultaneously adjust structural, magnetic, and electronic properties within a single architecture. We present a multivariate solvothermal method that utilizes the time–temperature–solvent (T–T–S) synthesis space to fabricate zinc–iron bimetallic metal–organic frameworks (ZnFe-MOFs) based on the Fe^III–MIL-88B (MIL – Materials of Institute Lavoisier) structure. The systematic alteration of reaction duration (12–48 hours), temperature (100–140 °C), and solvent polarity (N,N-dimethyl formamide (DMF)/ethanol) facilitates precise regulation of lattice expansion–contraction (“breathing”), metal-site distribution, and crystallographic orientation. Powder X-ray diffraction (PXRD) revealed that Zn^II incorporation enhances structural stability and induces preferential growth along the (101) plane. Electronic modulation through Zn²⁺ substitution effectively inhibits Fe³⁺ mediated non-radiative decay processes, resulting in a significant increase in ligand-centered fluorescence. Meanwhile, glutathione depletion assays, electron paramagnetic resonance (EPR) spectroscopy, and magnetic force microscopy verify the retention of Fe-centered redox activity and the integrity of nanoscale magnetic domains. The designed optical–redox framework results in superior electrocatalytic efficacy: ZnFe-MOF-modified electrodes provide a detection limit of 0.043 µM, a linear range of 10–1000 µM, and a sensitivity of 66.24 µA µM⁻¹ cm⁻² for dopamine oxidation, exhibiting significant selectivity against prevalent interferents. These findings demonstrate that bimetallic synergy-driven structural modulation provides an effective design strategy for metal–organic frameworks, enabling enhanced optical emission, retention of magnetic functionality, and improved redox-active sensing performance.