Journal of materials chemistry. B最新文献

The development of stimuli-responsive amphiphilic block copolymers and their nanoassemblies/nanogels integrated with degradable covalent chemistry undergoing chemical transitions has been extensively explored as a promising platform for tumor-targeting controlled/enhanced drug delivery. The conjugate aromatic imine bond is unique in responding to acidic pH through acid-catalyzed hydrolysis and visible light through photo-induced E/Z isomerization, thus allowing for a dual acid-light response via a single conjugate aromatic imine bond. Herein, we report a robust strategy for fabricating well-defined core-crosslinked nanogels bearing extended conjugate aromatic imine linkages that exhibit controlled degradation in response to acidic pH and visible light. This approach utilizes the pre-crosslinking of a poly(ethylene glycol)-based block copolymer bearing reactive imidazole pendants with a diol crosslinker bearing an extended conjugate aromatic imine, followed by the mechanical dispersion of the formed crosslinked polymers in an aqueous solution. The fabricated core-crosslinked nanogels with a hydrodynamic diameter of 119 nm are non-cytotoxic, colloidally stable, and capable of encapsulating cancer drug curcumin. They exhibit controlled/enhanced release of encapsulated curcumin at pH = 5 (acidic) or upon irradiation with visible light (λ = 420 nm) as well as exhibit promisingly accelerated and synergistic release under the combination of the above conditions. Furthermore, curcumin-loaded nanogels reduce cell viability in a controlled manner, unlike free drugs. This simplified yet efficient synthetic approach paves the way for the development of smart nanocarriers with potential applications in controlled drug release and cancer therapy.

Self-powered piezoelectric materials can generate continuous electrical stimulation in response to weak mechanical forces, holding great potential for accelerating wound healing. Herein, a multifunctional ZIF-8/PVDF piezoelectric fiber dressing was fabricated using the electrospinning method for generating electrical stimulation to enhance the endogenous electric field at the wound site. The incorporation of ZIF-8 nanoparticles and the stretching polarization effect of electrospinning on the fibers promote the formation of the piezoelectric β-phase in PVDF, leading to enhanced piezoelectricity. The improved piezoelectric and conductive properties collectively enhance the output electrical signals of the fiber. The short-circuit voltage and open-circuit current of the 5% ZIF-8/PVDF fiber were 2.97 V and 13.7 nA, respectively, showing significant improvement compared to the pure PVDF fiber. In vitro experiments demonstrate that the fiber can generate reactive oxygen species (ROS) and release Zn²⁺ under ultrasonic conditions, which together with electrical stimulation endows the dressing with effective antibacterial, anti-inflammatory, and angiogenic effects. In vivo studies of infected skin defect models demonstrated that the ZIF-8/PVDF fiber dressing can significantly inhibit bacterial infection, regulate inflammatory responses, enhance angiogenesis, and ultimately accelerate the infected wound healing process. This developed multifunctional piezoelectric fiber dressing provides an effective strategy for infected wound repair.

Polymer nanotherapeutics have gained prominent attention in drug delivery systems. Polymers are widely explored tools to improve the solubility, stability, bioavailability, and prolonged circulation of therapeutic agents. Abraxane, Myocet, DaunoXome, and Doxil are some examples of successful polymeric nanocarriers approved for cancer treatment. Medicinal chemists have access to a vast array of nanomaterials that include polymeric nanoparticles (PNPs), polymeric micelles (PMCs), prodrugs, liposomes, and dendrimers. Polyethylene glycol (PEG), pHPMA (poly-N-2 hydroxypropyl methacrylamide), polyethylene, polystyrene, and other compounds have been extensively used for drug delivery. This review highlights the importance of pHPMA in nanodrug delivery. First, we review the chemical properties, pharmacology, and pharmacokinetics of pHPMA, followed by its synthetic routes of preparation. Second, we discuss pHPMA-based nanocarriers and their therapeutic efficacy in cancer. In addition, we present the clinical status and future prospects of pHPMA in combination with immunotherapy. We aim to provide comprehensive insights into the current pHPMA nanotherapeutics to facilitate future development.

Bacterial biofilms remain a major challenge in treating persistent infections due to their dense extracellular matrix and inherent antibiotic resistance. Herein, we propose a light-responsive nanoparticle system (PNO@Ir) that integrates a nitric oxide (NO) donor polymer (PNO) with the photosensitizer fac-Ir(ppy)₃. Upon green light irradiation, NO release and activation of primary amine-containing antibacterial polymers are triggered via a dual mechanism involving triplet-triplet energy transfer (TTET) and photoinduced electron transfer (PeT). Under mildly acidic and hypoxic conditions, protonation of the exposed amines induces nanoparticle reorganization, leading to surface charge reversal and enhanced bacterial affinity. Both in vitro and in vivo studies, including a murine wound infection model, demonstrate that this cascade-activation strategy disrupts methicillin-resistant Staphylococcus aureus (MRSA) biofilms. This work presents a synergistic and spatiotemporally controllable platform for NO delivery and antibacterial polymer activation, offering significant potential for combating antibiotic-resistant bacterial infections.

Hollow fiber membranes (HFMs) are critical components in hemodialysis and bioartificial kidney (BAK) applications, with ongoing research focused on optimizing biomaterials for improved performance. In this study, polyethersulfone (PES) HFMs were modified by incorporating titanium dioxide (TiO₂) and graphene oxide (GO) during the spinning process. This approach leverages the non-toxicity, hydrophilicity, and dispersion stability of TiO₂ alongside the large surface area of GO to enhance membrane properties. Characterization and performance evaluations demonstrated that TiO₂/GO-doped PES HFMs exhibit superior biocompatibility and hemocompatibility compared to plain PES, TiO₂/PES, and GO/PES membranes. Confocal microscopy revealed improved HEK293 cell attachment and proliferation, corroborated by MTT assays showing higher cell viability and flow cytometry indicating no cytotoxic effects. Hemocompatibility tests confirmed negligible hemolysis and anti-inflammatory properties, making the membranes suitable for blood-contacting applications. Furthermore, separation performance analyses highlighted TG(0.5/1.5) as the optimal composition, offering a balance of enhanced toxin removal and cell compatibility. These findings establish TiO₂/GO-doped PES HFMs as promising candidates for BAK and hemodialysis, combining excellent biocompatibility, hemocompatibility, and separation efficiency.

N-Methyl-D-aspartate receptor (NMDAR)-antibody-labeled mesoporous silica nanoparticles (NMDAR-PEG-DID@MSNs) were developed as a fluorescence imaging tool for M1 macrophage-associated inflammatory diseases. The nanoparticles were synthesized by conjugating NMDAR antibodies, polyethylene glycol (PEG), and the fluorescent dye DID onto mesoporous silica nanoparticles. Their imaging capability was evaluated in chronic (turpentine induced) and acute (lipopolysaccharide and carrageenan-induced) inflammation models, as well as for monitoring the anti-inflammatory effects of dexamethasone. NMDAR-PEG-DID@MSNs enabled the early detection of inflamed lesions, with fluorescence signals persisting for up to 24 hours, and successfully demonstrated the therapeutic efficacy of dexamethasone. These results highlight the potential of this nanoplatform for inflammation diagnosis and therapeutic monitoring.

Quantitative assessment of pore size and morphology is crucial in biomaterials design and evaluation, particularly hydrogels and scaffolds used in tissue engineering and drug delivery. In recent years, a growing number of studies have proposed or adopted automated image analysis tools to evaluate pore characteristics; however, the absence of standardised protocols, validation criteria, and consistent reporting practices has limited reproducibility and cross-study comparability. This perspective, for the first time, examines recent trends in automated pore size analysis in biomaterials research, highlighting commonly used algorithms, their implementation in image-based workflows, and their ability to resolve pore geometries in disordered materials. We discuss the influence of imaging dimension, resolution, algorithm assumptions, and image pre-processing on outcomes and highlight common challenges such as over-segmentation, user bias, and the misidentification of irregularly shaped pores. By drawing on selected examples from the literature, we illustrate both the strengths and limitations of current approaches and emphasise the need for transparent, standardised methodologies in the field.

Iron-gallic acid chelate nanoparticles (Fe-GA NPs) have emerged as promising Fenton catalysts and drug carriers in oncology. However, their therapeutic efficacy remains constrained by tumor microenvironment (TME) limitations - suboptimal pH and insufficient endogenous hydrogen peroxide. To overcome these barriers, we engineered an ATP-responsive core-shell nanoarchitecture (GOx@Fe-GA) integrating glucose oxidase (GOx) with Fe-GA coordination networks. Upon encountering elevated ATP concentrations in tumor cells, the nanosystem undergoes programmed disassembly: released GOx depletes glucose to induce metabolic starvation while generating substantial H₂O₂ and acidifying the TME, thereby creating ideal conditions for Fe-GA-mediated Fenton reactions. Simultaneously, Fe-GA acts as a photothermal agent under near-infrared irradiation, leading to mild hyperthermia that synergizes with reactive oxygen species (ROS) to overcome thermotolerance by disrupting heat shock protein (HSP70) defenses. Both in vitro and in vivo studies showed potent tumor suppression with minimal systemic toxicity. These studies establish GOx@Fe-GA as a self-enhancing therapeutic platform. Here, tumor-specific ATP triggers a cascading therapeutic amplification involving an ROS storm, metabolic deprivation, and photothermal sensitization.

Ultrasound (US) offers exceptional tissue penetration, making it a promising modality for the treatment of deep-seated cancers. Sonodynamic therapy (SDT) leverages US to activate low-toxicity sonosensitizers, generating cytotoxic reactive oxygen species (ROS) that induce cancer cell death. However, its clinical effectiveness is hindered by challenges such as hypoxia and overexpression of glutathione (GSH) in the tumor microenvironment (TME). In this study, we designed and synthesized a sodium-hyaluronate-modified TCCP-BSO@CaO₂@SH nanoplatform (TBC@SH NPs) to enhance SDT efficacy in hepatocellular carcinoma (HCC). The TBC@SH NPs were prepared through a straightforward one-pot method, involving the self-assembly of CaO₂ nanoparticles with tetrakis (4-carboxyphenyl) porphyrin (TCPP) and L-buthionine sulfoximine (BSO), followed by surface modification with sodium hyaluronate (SH) for targeted delivery to CD44 receptors on HCC cells. In the mildly acidic TME, TBC@SH NPs facilitate oxygen release, induce calcium ion overload, inhibit GSH synthesis, and generate substantial reactive oxygen species (ROS) under ultrasound irradiation. These synergistic effects collectively amplify oxidative stress, significantly enhancing SDT therapeutic efficacy in HCC treatment. Encouraging results were observed in both in vitro HCC cell models and in vivo animal tumor models. This study highlights the potential of ultrasound-mediated SDT therapy for HCC and provides valuable insights into the development of integrated nanoplatforms for enhanced HCC treatment.

The development of advanced biomaterials with multifunctional properties is essential to address the complex challenges of impaired wound healing and tissue regeneration. This study introduces a novel composite scaffold (SSP-CG), in which silk sericin (SS) and polyvinyl alcohol (PVA) form the SSP component, while copper nanoparticles (CuNPs) and gallic acid (GA) constitute the CG component. SS provides biocompatibility and biodegradability, while PVA enhances structural integrity. CuNPs and GA impart antimicrobial and antioxidant activity, respectively, making the scaffold highly suitable for biomedical applications. The scaffold features an optimal pore size (96 ± 19 μm) and pore volume, promoting cell infiltration and nutrient diffusion. In vitro degradation studies revealed a controlled, sustained profile over 6 weeks, ideal for long-term therapeutic use. A gradual and prolonged release of GA ensured continuous antioxidant activity, confirmed by a DPPH assay showing significant free radical scavenging activity (40.5 ± 2.1%). In vitro studies further confirmed excellent biocompatibility, with optimal cell adhesion, proliferation, and viability while maintaining the environment for tissue regeneration. In vivo studies demonstrated superior wound healing outcomes for the SSP-CG scaffold compared to both positive and negative controls, with histological analysis further confirming enhanced tissue regeneration and reduced inflammation. This first-of-its-kind integration of SS, PVA, CuNPs, and GA highlights the synergistic benefits of these components, offering a promising solution for advanced wound healing and tissue regeneration. These findings suggest that SSP-CG scaffolds could contribute to next-generation biomaterials tailored for chronic wound management and regenerative therapies.