Biomaterials Science最新文献

This study addresses the critical clinical challenge of implant failures due to mechanical overload by developing a novel rat model to investigate re-osseointegration. Metal implants, essential in dental, maxillofacial, and orthopaedic treatments, rely on osseointegration for stability. However, the fate of mechanically overloaded implants remains poorly understood. We introduced intentional traumatic loosening of submicron-modified titanium implants (treated with NaOH) through snap rotational overload in rat tibiae. After four weeks of initial healing, implants were disrupted and then allowed to re-heal for another four weeks. Evaluations using removal torque, histology, histochemistry, and Raman spectroscopy demonstrated successful re-healing with regained mechanical stability, bone–implant contact, and bone volume. Dynamic histology revealed bone tissue remodelling near the implant interface, indicating fractures due to mechanical disruption. These findings confirm that osseointegrated implants can re-heal under normal conditions. The validated rat model offers a controlled platform for future studies on re-osseointegration following traumatic mechanical overload. The potential applications of this experimental model may extend to investigating compromised healing conditions, early/direct loading conditions, and the cellular and molecular mechanisms involved in peri-implant bone repair.

Correction for ‘Ultra-low attachment surface enabling 3D co-culture of human B cells with CD40L-expressing stromal cells for in vitro mimicry of secondary lymphoid organs’ by Ananta Kumar et al., Biomater. Sci., 2025, https://doi.org/10.1039/d5bm01039j.

Activation of hepatic stellate cells (HSCs) is a key driver of fibrogenesis, while perisinusoidal collagen I deposition establishes biophysical barriers that impede therapeutic delivery. To address this challenge, we developed a cationic liposome nanomicelle system (LIP/RSC) based on a polyenyl phosphatidylcholine (PPC) matrix, functionalized with collagenase I and dual silybin B-retinoic acid (silybin-RA) moieties. In this design, retinoic acid (RA) was covalently conjugated to two distinct components: (i) silybin B to form a targeted therapeutic complex (silybin-RA), and (ii) DSPE-PEG2000-NH₂ to construct a long-circulating carrier (RA-DSPE-PEG2000). The resulting system embodies an innovative HSC-ECM dual-targeting strategy through the integration of dual RA modification technology—combining silybin B-targeting modification with DSPE-PEG2000 long-circulation modification—and spatiotemporally controlled silybin B release. The LIP/RSC system exhibited cell-selective drug release profiles, with a 4-fold greater release of silybin B in CCl₄-activated HSCs (LX-2-CCl₄) than in hepatocytes (WRL68), accompanied by collagen normalization. The system conferred dual pharmacodynamics: slow-release kinetics-prolonged circulation time (≥72 h) while enabling receptor-mediated HSC targeting and collagenase I activity-enhanced fibrotic barrier penetration, resulting in a 2.1-fold increase in the silybin B release efficiency in 8–72 h post-injection and an 85% reduction in the total collagen content in fibrotic murine models. This study validates LIP/RSC as an integrated nanoplatform that synergizes matrix remodeling with targeted drug delivery, thereby demonstrating enhanced therapeutic efficacy against hepatic fibrosis.

The targeted detection of cancer cells is crucial for tumour diagnosis and therapeutic treatment. Recently, luminescent carbon dots have generated wide interest in biomedical applications, thanks to their unique properties such as biocompatibility, tuneable emission, water solubility and the possibility of surface functionalization. Herein, we report the conjugation of red emitting carbon dots (RCDs) to alginate and the sTN58 aptamer to obtain systems able to selectively recognize cancer cells that can be exploited in bioimaging and potentially as photothermal agents.

Bacterial membrane vesicles (MVs) are a heterogeneous group of lipid-bound structures produced by bacteria. Antibiotic stress aggravates the secretion of MVs that contributes to the development of bacterial antibiotic resistance. This review provides a focused, resistance-oriented perspective on the interplay between MVs and antibiotic resistance. We outline MV biogenesis, emphasizing the distinct formation mechanisms of Gram-negative and Gram-positive bacteria. We further focus on the secretion of MVs under antibiotic stress, highlighting pathways such as bacterial envelope stress, SOS response, and cell wall disruption. The pivotal role of MVs in bacterial antibiotic resistance is also elucidated, including neutralizing antibiotics, absorbing phages, and facilitating drug efflux, biofilm formation, and horizontal gene transfer. Current challenges and future prospects for elucidating MV-mediated mechanisms in antibiotic resistance are discussed.

Cancer is the second most common cause of death worldwide, with its origin in cells abnormal growth. Available chemotherapeutics present major drawbacks, usually associated with high toxicity and poor distribution, with only a small fraction of the drug reaching the tumour site. Nanoparticles, particularly dendrimers, are paving the way to the front line of cancer treatment, primarily for drug and gene delivery, diagnosis, and disease monitoring. In the present work, we demonstrate the intrinsic anticancer activity of two polycationic core–shell PURE biodendrimers, PURE_G4-OEI₄₈ and PURE_G4-OCEI₂₄, designed as synthetic mimics of anticancer peptides (SMACPs), and evaluate their action against several cancer cell lines. Our findings show that PURE_G4-OEI₄₈ disrupts cell membrane integrity, interacts with mitochondria, and induces cell death by promoting apoptosis, as indicated by Annexin V⁺/PI⁺ cells when incubated with the IC₅₀ concentration. PURE_G4-OCEI₂₄, which is more hydrophobic and less cationic than PURE_G4-OEI₄₈, exhibits cytotoxic effects on cancer cells and inhibits wound healing after 24 hours, and its mechanism of action may be partially associated with cell necrosis. Based on our results, we conclude that both core–shell polycationic PURE dendrimers target the mitochondrial membrane, activating distinct cell death mechanisms.

The discovery of exosomes in the early 1980s transformed modern medicine by establishing a new class of cell-free therapeutics. Exosomes, which are classified as diminutive membrane-bound vesicles, are secreted by all cell types in the extracellular space. Functionally, they are involved in intercellular communication and transport bioactive cargoes across the cells. Recently, exosomes have gained attention for their potential in the treatment and diagnosis of osteoarthritis (OA). Stem cell-derived exosomes are known to promote cartilage regeneration and reduce inflammation, while endogenous exosomes from osteoarthritic cells exacerbate the progression of OA. Despite their therapeutic potential, the low retention of exosomes administered intra-articularly in the joint cavity limits their application. Hydrogels, as a delivery vehicle for exosomes, allow them to achieve an increased residence time and sustained and localized release within the osteoarthritic joint. Furthermore, hydrogels protect exosomes from enzymatic degradation, mimic the extracellular matrix, and enhance their bioavailability and regenerative potential. This review provides an overview of the biogenesis of exosomes and key techniques for exosome isolation and characterization. We also discuss their functional role in therapy and the pathogenesis of OA. Additionally, we highlight the diagnostic value of exosomal miRNAs, lncRNAs, and circRNAs as emerging biomarkers for OA. Furthermore, we spotlight recent research in developing exosome-loaded hydrogels for OA treatment, focusing on their therapeutic outcomes, encapsulation, and characterization. Finally, we discuss current difficulties and prospects for translating exosome-loaded hydrogels into clinical settings.

Anastomotic leaks are among the most severe side effects following abdominal surgeries. Conventional surgical sealants and emerging hydrogel adhesives often lose mechanical and adhesion strength when exposed to leaked digestive enzymes. Here, we report a tannin-encapsulating tough hydrogel adhesive that exhibits enhanced mechanical and adhesive properties upon the encounter of leaked proteins. The hydrogel is composed of a gelatin–acrylate crosslinked network with encapsulated tannin and can adhere to a wet surface via amine–carboxyl chemistry. In the context of anastomotic leaks, tannin within the hydrogel can form a complex with proteins including the digestive enzymes, leading to increased gel stiffness and storage modulus. The enhanced mechanical strength confers improved adhesive properties on the hydrogel adhesive. Additionally, the tannin-bearing hydrogel adhesive shows excellent antibacterial properties. This adaptive and antibacterial hydrogel adhesive provides a promising sealant for gastrointestinal surgery and other applications.

The delayed healing of alveolar bone defects caused by periodontitis remains a thorny problem. Here, we developed a kind of natural hydrogel, Cu/Zn-FG, synthesized based on the formation of a hydrogel network triggered by thrombin and the coordination bond between the fibrin and metal ions. The characteristics of Cu/Zn-FG were evaluated using the following methods: morphological observation, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The anti-inflammatory effect and osteogenic differentiation potential of Cu/Zn-FG were also assessed on the RAW264.7 and MC3T3-E1 cells. Moreover, Cu/Zn-FG's in vivo therapeutic efficacy was evaluated in a rat model of periodontitis. The results demonstrated that Cu/Zn-FG could release copper and zinc ions for 26 hours as the protease activity increases in the infection microenvironment, and these ions can maintain their biological activity in vitro. Furthermore, we found that Cu/Zn-FG can effectively inhibit the growth activity of Porphyromonas gingivalis (P. gingivalis), promote osteogenic differentiation of MC3T3-E1 and regulate the expression of inflammatory factors of RAW264.7. In the process of the in vivo experiment, periodontitis rats treated with Cu/Zn-FG revealed that bone regeneration was accelerated. Our study confirms that Cu/Zn-FG is an innovative material that could promote alveolar bone regeneration in a rat model of periodontitis, exhibiting its translational potential for clinical application and providing a new therapeutic strategy in the treatment of periodontitis.

The escalating prevalence of drug-resistant microbes coupled with their persistence in mono- and polymicrobial biofilms impose a critical healthcare challenge. Metal nanoparticles, particularly silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs), offer potent antimicrobial activity but face limitations due to their complex synthetic protocols, reliance on external reducing agents and surfactants, resulting compromised biocompatibility and poor in vivo outcomes. Herein, we present a facile, biocompatible approach for synthesizing antimicrobial supramolecular nanocomposite hydrogels (ASNH) via a one-pot, aqueous process that enables in situ growth of AgNPs and AuNPs through supramolecular interactions with short peptides. Utilizing sunlight photoirradiation, these hydrogels eliminate external reducing agents while serving as stabilizers for nanoparticle formation. The metallohydrogels exhibit rapid and broad-spectrum antimicrobial activity, against multidrug resistant bacteria and fungi. In addition to disrupting single species biofilms, the optimal hydrogels significantly eradicate polymicrobial biofilms formed by MRSA and Candida albicans. The hydrogels achieve ≥1.5-log reduction in microbial viability, outperforming last resort antibiotics and commercial silver-based ointments. In vivo studies demonstrate accelerated wound healing by reducing bacterial burden and mitigating inflammatory responses, while enhancing neovascularization, granulation, fibroblast proliferation, collagen deposition and epithelialization. The mild, economical synthesis and robust antimicrobial efficacy of these peptide-based metallohydrogels underscore their clinical potential as next-generation biomaterials for polymicrobial biofilm-associated infections.