Journal of Materials Chemistry B最新文献

Amphiphilic nanogels (ANGs) are promising colloidal carriers to improve bioavailability of poorly water-soluble drugs. In contrast to conventional hydrophilic nanogels, ANGs contain additional hydrophobic domains in their network to load hydrophobic cargos. However, optimizing drug loading remains labour-intensive due to the lack of quantitative tools that accurately capture the complex ANG–drug interactions. To address this limitation and assess drug compatibility, we developed a quantitative framework based on Flory–Huggins interaction parameters (χ). Key to our approach is the empirical adjustment of the correction factor α to account for unequal contributions of dispersion forces, polar interactions, and hydrogen bonds. Using a model ANG and a library of hydrophobic drugs and dyes, we established selection rules for α based on the dominant interaction type: α = 1 for dispersion-dominated, α = 0.7 for polar, and α = 0.3 for hydrogen bond-dominated systems. This enabled systematic grouping of cargos and revealed strong monotonic negative correlations between adjusted χ values and experimental loading capacities. The resulting universal calibration curve links χ to drug loading content across diverse ANG–drug systems. Consequently, our framework suggests predictive potential of solubility parameter-based models, reduces experimental burden, and supports the rational design of ANG carriers tailored to specific hydrophobic drugs.

NADH and NADPH are essential coenzymes involved in diverse biochemical processes and their deregulated levels are closely linked to various pathological conditions in eukaryotic systems. Accurate determination of NAD(P)H levels under physiological conditions is therefore critical for elucidating their biological functions and roles in disease. In this study, we present an NIR-emissive, cationic iridium-based aggregation-induced emission (AIE) probe (Ir2), functionalized with an imidazolium moiety, for the sensitive and selective detection of NAD(P)H. Ir2 exhibited excellent sensitivity, with limits of detection of 3.6 nM for NADPH and 6.2 nM for NADH in aqueous media. The probe's positive charge facilitates strong electrostatic interactions with the negatively charged NAD(P)H, while the imidazolium group promotes the formation of Ir2–NAD(P)H aggregates, resulting in aggregation-induced luminescence enhancement. Ir2 also showed high selectivity for NAD(P)H over other biologically relevant species and retained functionality across physiological pH ranges (7–10), supporting its potential for intracellular imaging. Moreover, Ir2 selectively accumulates in mitochondria and effectively monitors NADH levels in living cells. These findings highlight the promise of Ir2 as a valuable tool for detecting NAD(P)H in both aqueous and biological environments.

Conductive hydrogels are promising candidates for neural bioelectrodes due to their softness, ionic permeability, and reduced mechanical mismatch with neural tissue. However, pristine biopolymer matrices such as alginate–gelatin (Alg–GEL) lack sufficient electrical functionality. Here, Alg–GEL hydrogels incorporating PEDOT:PSS, polypyrrole (PPy/PSS), or both were developed via blending and in situ polymerization, yielding a tunable family of soft, electroactive materials. The hydrogels exhibited Young's moduli of 5–70 kPa, depending on polymer loading, while electrical conductivities ranged from 0.1 to 3.7 S cm⁻¹, with the highest values observed in PEDOT–PPy hybrids. Electrochemical measurements showed impedance values of 380–830 Ω cm² at 1 kHz, an electrochemical stability window of approximately −0.85 to +1.2 V vs. Ag/AgCl_sat, and current injection limits reaching 4 mA, comparable to platinum electrodes. Swelling studies indicated that PEDOT-modified hydrogels achieved 41–56% swelling after 24 hours. PPy-based hydrogels swelled to approximately 97% and hybrid systems showed behavior dependent on their composition. All conductive formulations demonstrated improved long-term stability compared to pristine Alg–GEL, which gradually lost mass over 28 days of incubation. In contrast, hydrogels containing PEDOT and PPy maintained nearly constant wet weight, consistent with the formation of interpenetrating networks that prevented polymer degradation and leaching. Biological evaluation with NIH3T3 fibroblasts showed that all hydrogels were cytocompatible. PPy-only and PPy–PEDOT hybrids supported higher metabolic activity and more attached and spread cells after 7 days compared to Alg–GEL, while PEDOT-only samples showed similar or slightly reduced cell activity. These results confirm excellent cytocompatibility and suggest that PPy-rich domains improve cell–material interactions. Overall, PEDOT- and PPy-modified Alg–GEL hydrogels offer high conductivity, softness, electrochemical stability, long-term durability, and biocompatibility, creating a versatile and adjustable platform for next-generation soft neural interfaces.

Correction for ‘A dual aperture (mesoporous and macroporous) system loaded with cell-free fat extract to optimize bone regeneration microenvironment’ by Enhui Qiu et al., J. Mater. Chem. B, 2023, 11, 826–836, https://doi.org/10.1039/D2TB01980A.

Ischemic stroke remains one of the leading causes of long-term disability worldwide, depriving patients of their quality of life and physical independence. The root cause of this loss of motor movement stems from the disruption of neuronal connections in the infarct site. Limited spontaneous neural re-wiring post-stroke does provide limited functional recovery, but more than two thirds of ischemic stroke patients suffer from long-term disability for the remainder of their lives. Here, we explore the co-delivery of synaptogenic proteins with an angiogenic biomaterial to promote synapse formation in a mouse model of ischemic stroke. The angiogenic biomaterial is based on microporous annealed particle (MAP) scaffolds containing previously reported pro-angiogenic clustered vascular endothelial growth factor (CLUVENA) heparin nanoparticles. To this material, pro-synaptogenic protein thrombospondin-1 (TSP-1) was added either in soluble or clustered nanoparticle form. Co-delivery of TSP-1 with CLUVENA within MAP scaffolds led to enhanced synapse formation in and around the infarct, despite a reduction in axonal sprouting when compared to CLUVENA delivery alone. TSP-1 treatment also resulted in increased glial scar thickness and astrocytic coverage in the peri-infarct region, potentially contributing to limited axonal integration. Overall, these findings highlight the capacity of TSP-1 to modulate the synaptic and glial landscape post-stroke.

Acne is a common chronic inflammatory skin disease associated with Cutibacterium acnes (C. acnes). Although photodynamic therapy (PDT) effectively improves acne, the transdermal delivery of photosensitizers and limited light penetration through the skin restrict its therapeutic efficacy. In this study, we developed a dual-functional flexible microneedle patch using 3D printing technology, capable of simultaneously delivering the photosensitizer 5-aminolevulinic acid (ALA) and blue light. The microneedle patch exhibits favorable mechanical properties (a fracture force of 2.47 N per patch and a drug loading capacity of 655 ± 0 µg per patch) and increases the light penetration depth in tissue by 128.6%. The combination of the microneedle patch and blue light achieved an antibacterial rate of 97.10 ± 1.1% against C. acnes in vitro. In animal experiments, this strategy resulted in significantly smaller acne lesions by day 7 (size: 1.53 ± 0.30 mm; thickness score: 0.20 ± 0.45; n = 5 per group, P < 0.05), with no significant adverse effects observed during the experimental period. Our preclinical findings demonstrate that this dual-function microneedle patch provides proof-of-concept for its future development as a novel integrated platform for PDT.

Breast cancer recurrence and therapeutic resistance are primarily driven by breast cancer stem cells (bCSCs), which are poorly eliminated by conventional chemotherapy. To address this limitation, we developed an in situ-forming injectable silk hydrogel for sustained dual delivery of doxorubicin (DOX) and salinomycin (SAL), enabling concurrent targeting of bulk tumor cells and bCSCs. The hydrogel forms under physiological conditions without the need for UV irradiation or toxic initiators and exhibits tunable mechanical and degradation properties. An optimized 8% hydrogel exhibited controlled release behavior of DOX and SAL, characterized by a limited initial burst followed by sustained release for up to 30 days. In vitro viability assays demonstrated that DOX or SAL alone reduced cancer cell viability by approximately 45–55%, whereas the dual-drug loaded hydrogel (SilkVS-DOX + SAL) achieved a cytotoxicity of roughly 90%. Mammosphere formation assays demonstrated a marked reduction in both mammosphere number and size, indicating potent inhibition of bCSC self-renewal. Consistently, expression of bCSC-associated stemness markers was reduced by approximately three-fold relative to free-drug treatments. Flow cytometric analysis further confirmed enhanced induction of apoptosis within the bCSC-enriched population following treatment with SilkVS-DOX + SAL. In vivo studies using 4T1 tumor-bearing mice demonstrated that the localized, sustained release of DOX and SAL from the injectable silk hydrogel synergistically suppressed tumor growth, while significantly reducing systemic toxicity compared to individual drug administration. Overall, the in situ silk injectable hydrogel with sustained dual-drug release effectively eliminates both bulk tumor cells and bCSCs, making this injectable silk hydrogel a promising strategy for reducing breast cancer stem cells, which may reduce the chances of recurrence and enhance therapeutic outcomes.

Photocleavable protective groups (PPGs) offer a straightforward method of temporarily masking the aggressive functions of organic compounds and inactivating biologically active or toxic substrates. The active species can then be released from their photoactivatable precursors in a controlled manner upon exposure to light. In this study, we present a series of photocages based on the novel fluorescent scaffold 2-aryl-2H-1,2,3-triazol-4-yl-thiazoles (ATTs), incorporating proteinogenic amino acids, the biologically active compound biotin, the anticancer agent melphalan, and model compounds such as aromatic acids. Studies of photodegradation under various conditions using mass spectrometry, spectral and kinetic analyses, and quantum mechanical calculations have shown that acid release from the photoconjugates (ATT-PCs) depends on fluorophore fragment structure, acid nature, and the presence of air, water or a phosphate buffer solution (pH of 7.4), as well as the light source power and λ_ir. The release of acid during photodissociation was confirmed through high-resolution mass spectrometry and biological experiments, including the MTT assay and the imaging of Vero cells incubated with ATT-PCs, utilising a confocal scanning microscope. The photorelease mechanism was explored using both experimental studies and quantum mechanical calculations, which revealed that the properties and reactivity of this photosystem are predominantly influenced by the transition to the triplet state. Additionally, the findings indicated that ATT-PCs effectively absorb light in the visible spectrum and exhibit intense fluorescence, even in a DMSO–PBS mixture at a 1 : 9 ratio. Furthermore, ATT-PCs can function as photosensitisers, capable of generating reactive oxygen species (ROS). Cell studies demonstrate the rapid intracellular uptake of ATT-PCs by Vero cells, with accumulation in the endoplasmic reticulum (ER) or lipid droplets within a 0.5-hour incubation period.

The design of new antimicrobial materials is a critical challenge in chemistry and materials science, driven by the global threat of multidrug-resistant pathogens. Ionic liquids (ILs) represent a highly versatile class of materials, where their chemical structure can be systematically designed to achieve desired functions. However, a significant hurdle in their application as antimicrobial agents is the inherent trade-off between antibacterial efficacy and host toxicity. This review addresses this materials design challenge by focusing on the use of machine learning (ML) to guide the chemical design of ILs. We provide a comprehensive overview of the chemical mechanisms that drive both the desired antimicrobial activity and the undesired toxicity. We then detail how an understanding of these structure–property relationships is being leveraged to build predictive quantitative structure–toxicity relationship (QSTR) models. A central focus is the application of ML for multi-objective optimization, which allows for the rational design and virtual screening of ILs with optimal efficacy–toxicity profiles. By connecting the design of cationic and anionic structures to biological outcomes, this review offers a forward-looking perspective on the data-driven chemical design of the next generation of antimicrobial materials, highlighting the synergy between materials chemistry and computational science.

The reconstruction of critical-size skull defects is challenged by the limited availability of autologous bone grafts and the mismatch between degradation rate and new bone formation in synthetic scaffolds. Wollastonite (CaSiO₃; CSi), despite its favorable bioactivity, suffers from rapid degradation and inadequate structural stability, hindering its clinical application. In this study, we conducted systematic parameter optimization by fabricating a series of 3D-printed wollastonite scaffolds with uniform phosphate-doping levels (CSi-Px, where x = 0, 3, 6, and 9 mol%) via digital light processing (DLP). Our objective was to identify the optimal doping concentration that best balances the scaffold's degradation behavior with its osteogenic capacity. The scaffolds were characterized in terms of pore structure, compressive strength, in vitro degradation and re-mineralization capacity. Cell proliferation and osteogenic differentiation experiments were conducted using bone marrow mesenchymal stem cells (BMSCs). In particular, the bone regeneration efficacy was evaluated in a rabbit cranial defect model over a 12-week period. The results indicated that phosphate doping significantly promoted the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), enhanced the mineralization capacity of the scaffold, reduced the in vivo degradation rate of the calcium silicate scaffold, and maintained its structural and morphological stability, thereby providing improved osteoconductive capability. The phosphate content significantly influences bone repair outcomes by modulating the degradation behavior and bioactivity of CSi, and 6% phosphate doping is identified as the optimal content, which may balance the structural stability, biodegradation rate, and potent osteogenic capacity. This study provides quantitative design guidelines for developing calcium–silicon–phosphorus (Ca–Si–P)-based bioceramics.