UrolithiasisYe Jean Lim, Ye Na Diana Lim, Connor A Church, Elijah Haynal, Elizabeth A Baldwin, D Duane Baldwin
Silicone ureteral stents provide anti-encrustation properties and patient comfort but are more difficult to insert and remove due to increased surface friction. Applying zwitterionic coatings to silicone stents may reduce friction and facilitate stent placement and removal. This study compared the frictional forces of zwitterionic-coated silicone stents with commercial stents using benchtop models. The static and kinetic frictional forces of five ureteral stents were measured: bare silicone stent without coating (BS), single outer-coated zwitterionic silicone stent (Z1), double-coated (inner and outer) zwitterionic silicone stent (Z2), Black Silicone Filiform stent ("Black Beauty") (BB), and Universa Soft stent (US). Friction was assessed with a submerged guidewire model to isolate stent-guidewire friction and a porcine ureteral model to simulate intraoperative stent insertion and removal. Five trials per stent were performed using a force gauge integrated with an Arduino-controlled motor system. Statistical significance was assessed using linear mixed-effects models with stent type and trial as fixed effects and ureter specimen as a random intercept. Pairwise comparisons were adjusted using the Holm method. In the submerged guidewire model, Z2 had 99%, 47%, and 40% lower kinetic friction than BS, BB, and US, respectively. During stent insertion, Z2 had 71%, 43%, and 44% lower kinetic friction than BS, BB, and US, respectively. During stent removal, Z2 had 92%, 58%, and 60% lower kinetic friction than BS, BB, and US, respectively. Linear mixed-effects models demonstrated a significant effect of stent type for all six friction conditions (all p < 0.001). The double-coated (inner and outer) zwitterionic silicone stent (Z2) demonstrated the lowest frictional forces across all testing conditions. Zwitterionic surface modification may therefore reduce friction during silicone stent placement and removal.
Most existing wound dressings provide only passive hemostasis and protection, and lack robust bio-interactions, active coagulation capabilities, or pro-healing functions, often leading to prolonged bleeding, delayed repair or recurrent bleeding. This paper describes a multifunctional spongy dressing fabricated via thermo-aided citrate cross-linking of pullulan, incorporating tissue factor (TF, a potent physiological coagulation initiator) and collagen. The composite sponge featured an interconnected hierarchical porous structure (porosity >80%) for high blood absorption, along with favorable mechanical strength and shape-recovery property. Functional analysis demonstrated that TF encapsulation acceleratedin vitrowhole blood coagulation and reduced bleeding time and blood loss by ∼73.9% and ∼77.7% in a rat liver injury model, while collagen encapsulation promoted full-thickness skin wound healing. These effects stem from three synergistic mechanisms: pullulan's porous structure and large surface area enabling ample interactions with blood or the wound bed, TF amplifying extrinsic coagulation, and collagen inducing clot formation and tissue repair. Additionally, the sponge comprising multiple bio-derived components exhibited good biocompatibility. These findings establish the TF-incorporated cross-linked pullulan/collagen sponge as a highly promising platform for addressing heavy bleeding and orchestrating subsequent wound healing.
BiofabricationOliver Kopinski-Grünwald, Corinna Barella, Anastasiia Budaeva, Jason A Burdick, Nathan Carpentier, Justin Cooper-White, Nikolas Galensowske, Antonia Georgopoul…
Biofabrication is a multidisciplinary field that integrates diverse technologies to create three-dimensional structures composed of living cells, biomaterials, and other biological components. One of its main goals is the realization of functional tissue constructs with hierarchical architectures, as observed in native biological tissues, for applications in tissue engineering and regenerative medicine, as well as forin vitromodelling. Given its multidisciplinary nature, continued collaboration among experts from various scientific and technological disciplines remains essential to address the challenges ahead and to achieve the ambitious objectives of this rapidly advancing field. Reflecting on the progress made since the first bioprinting attempts, one can only envision the achievements that biofabrication may accomplish in the coming decades. Symposia such as the Alpine winter school for Biofabrication, bring together leading experts and early-stage researchers who collectively shape the future of the discipline through innovation and discussion. During the 2025 edition of the winter school, participants exchanged knowledge on current advances, challenges, and future perspectives in biofabrication. Guided by experts in this field, early-stage researchers discussed and summarized their views on five key topics: (i) the future of devices and technology in biofabrication, (ii) current trends and opportunities in material development, (iii) impact on society, ethics, and communication, (iv) applications and clinical translation, and (v) education and skillsets required for successful research. Their perspectives summarized here, address critical questions about future methodology, material development, and technological improvements that will continue to shape the evolution of biofabrication. Furthermore, aspects such as the impact on society, as well as the required skillset and education for future scientists working in the field are discussed.
BACKGROUND: Electrospun nanocomposite biomaterials are promising candidates for blood-contacting medical devices owing to their high surface area, tunable nanoscale morphology, and biomimetic replication of the native extracellular matrix. However, conventional hemocompatibility assessments rely heavily on biological assays. These methods require blood samples, specialized reagents, and consumables, thereby inherently increasing costs, resource demands, and laboratory waste. To mitigate these limitations, sustainable evaluation strategies that leverage physicochemical features are highly desirable. METHODOLOGY: In this study, we present a deep learning framework for predicting the hemocompatibility of electrospun nanofibres directly from scanning electron microscopy (SEM) images. Pretrained convolutional neural network models, namely VGG19, ResNet50, and InceptionV3, were fine-tuned to classify scanning electron microscopy (SEM) images of nanofibres as haemocompatible or non-haemocompatible. To ensure data robustness, an Albumentations-based augmentation strategy was implemented, and predictive reliability was further optimized using a majority-voting ensemble learning approach. RESULTS: Among the individual architectures evaluated, InceptionV3 demonstrated superior performance, achieving a precision of 0.98, a recall of 1.00, and an F1-score of 0.99. The ensemble model exhibited comparable robustness, reaching an overall accuracy of 99%. Furthermore, explainable AI (XAI) techniques, specifically LIME and Integrated Gradients, confirmed that the network's predictions were driven by physiologically relevant microstructural features of the nanofibres. CONCLUSION: This artificial intelligence-assisted, SEM image-based physicochemical approach offers an eco-friendly pre-screening strategy that significantly reduces reliance on blood-based assays and associated laboratory consumables. Ultimately, this framework aligns with ISO 10993 guidelines by using SEM-derived physicochemical information as a pre-screening tool to support subsequent biological evaluation, thereby enabling efficient, regulatory-compliant biomaterial development.
Science advancesSherina Malkani, Olivia Prado, Inkyung Kang, Kelly R Stevens
Engineered tissues offer great promise for therapeutic organ repair. Yet, biofabrication of organ-scale tissues can take hours or days for large constructs with geometric complexity, during which living cells in the construct lack vascular support. To address this, we developed an approach to accelerate biofabrication by embedding microreservoirs of evacuation reagents throughout geometrically patterned sacrificial agents. We call this approach Suspended Particles for Omnidirectional Template Sacrifice (SPOTS). We show that microparticles can serve as both structural impurities as well as depots for dissolution agents within sacrificial materials, both of which facilitate accelerated degradation of sacrificial materials and vascular templates. We used SPOTS to produce branched vascular networks in engineered tissue constructs. These networks support perfusion and endothelialization, improve the viability of human cells embedded in the construct, and support phenotype and function of human hepatocytes in the surrounding matrix. By accelerating biofabrication processes, SPOTS thus addresses a critical remaining challenge hindering translation of engineered tissues.
Macromolecular bioscienceM Londoño, C Castro, A Cañas, S Ruiz, J Pedraz, M Osorio
3D in vitro cancer models provide a more physiologically relevant representation of tumor architecture and cell-matrix interactions than conventional monolayer cultures. This study evaluated bacterial nanocellulose (BNC) as a scaffold for the 3D culture of colorectal cancer cells. BNC scaffolds were produced using paraffin spheres as porogens and subsequently characterized in terms of morphology, chemical structure, thermal stability, and mechanical properties. Human colorectal cancer cell lines SW480 and SW620, along with CHO-K1 cells, were exposed to BNC leachates and cultured on 2D and 3D BNC matrices. Cells grown on 2D BNC exhibited typical monolayer proliferation, whereas 3D matrices allowed cell infiltration and volumetric distribution, supporting multicellular organization and the formation of spheroid-like aggregates. Cell viability remained in both leachate and direct scaffold cultures. Genotoxicity assays showed low levels of DNA damage, with most cells displaying no detectable genotoxic effects, and mutagenicity tests revealed no significant differences compared to controls (p > 0.05). Overall, the results demonstrate that 3D BNC supports cell viability, multicellular organization, and genomic safety, highlighting its suitability as a biocompatible scaffold for in vitro 3D colon cancer models.
Journal of biomedical materials research. Part B, Applied biomaterialsZiqi Wang, Huan Zhou, Hongshui Wang, Xianyang Chen, Lei Yang, Chunyong Liang
Spinal cord injury (SCI) causes persistent neurological deficits because primary damage initiates dynamic secondary cascades that restrict endogenous repair. Functional biomaterials can bridge lesions, provide structural and biochemical support, guide axonal growth, and remodel the inhibitory microenvironment. However, their cues are generally static or slowly evolving and cannot match the changing pathological and electrophysiological states of injured tissue. Physical modulation complements these functions by delivering electrical, magnetic, ultrasonic, optical/photothermal, or mechanical cues that regulate neural excitability, inflammation, axonal growth, remyelination, and plasticity. Nevertheless, physical modulation alone may suffer from imprecise localization, variable tissue-level dosing, and insufficient structural support. This review examines integrated biomaterial-physical modulation strategies for SCI repair, focusing on material design, mechanisms, and translational challenges. Conductive hydrogels couple lesion support with localized electrical signaling, whereas compliant electrodes improve tissue conformity and charge delivery. Piezoelectric and magnetically responsive materials convert external inputs into localized electrical or mechanical cues. Optical/photothermal systems combine localized energy conversion with on-demand release, whereas engineered matrices link structural support to mechanotransduction. Across these strategies, biomaterials act as regenerative scaffolds and active interfaces that localize, transmit, convert, and sustain physical signals. Physical inputs dynamically regulate cellular and molecular responses within this material-supported environment. This integration couples structural reconstruction and microenvironmental regulation with spatiotemporally controlled biophysical signaling, constituting the central mechanistic basis of these integrated systems. Translation requires standardized tissue-level dosing, evaluation of degradation-dependent signal stability and biocompatibility, cross-species scaling, and validation in relevant large-animal models. Stimuli-responsive materials and closed-loop systems represent important future directions. Overall, benefit depends not on simply adding stimulation to a scaffold, but on engineering coordinated material-stimulus systems. In such systems, material design controls where, when, and how physical cues are delivered during spinal cord regeneration.
Macromolecular bioscienceYanan Tian, Na Li, Lin Zhu, Jiannan Wang, Yanfei Feng, Zhentan Lu, Minhao Xi, Renchuan You, Xiufang Li, Dong Wang
Silk nanofibrils (SNF) demonstrate substantial potential as biomedical materials and biomineralization templates as a result of their biocompatibility, biodegradability, and resemblance to ECM structural proteins. However, a typical drawback is that the domesticated silk nanofibrils lack sufficient biological functional sites such as cationic groups that are beneficial for increasing cell adhesion, inhibiting bacterial growth, and promoting mineralized deposition. In this study, we developed a cationic SNF with dual functionalities of antibacterial properties and enhanced biomineralization using natural polysaccharide chitosan (CS) and synthetic polymer polyethyleneimine (PEI). The successful cationization of SNF was demonstrated through zeta potential measurement, XPS analysis, and antibacterial performance testing. Compared with polyethyleneimine modification, the CS-modified SNF exhibited superior cytocompatibility, highlighting the advantages of functionalizing proteins with natural cationized polysaccharides. Furthermore, the CS-modified SNF significantly accelerated the biomineralization process, enabling the formation of a uniform flower-like hydroxyapatite structure within 3 days in a 1.5 times simulated body fluid. This study offers a facile strategy for the surface functionalization of natural silk nanofibrils, thereby expanding the application of silks as functional biomaterials.
Canadian journal of veterinary research = Revue canadienne de recherche veterinaireHsin-Tai Chen, Chao-Chang Chen, Chen-Hsuan Tai, Lih-Seng Yeh
The objective of this study was to determine whether ligation security in a standardized in-vitro vascular model is primarily influenced by tying force or filament configuration when comparing 2 commonly used suture materials: monofilament polydioxanone and pseudomonofilament polyamide. A standardized latex vascular model subjected to controlled intraluminal pressure (150 mmHg) was used. USP 2-0 sutures were applied using a 4-throw surgeon's knot at 5 predefined tying-force levels (6, 8, 10, 12, and 14 N). Three time intervals between the first and second throw (0, 10, and 20 s) were evaluated. A total of 300 ligations were tested. Leakage was defined as a detectable increase in distal pressure during a 30-second observation period. The effects of tying force, time interval, and suture material were analyzed using multivariate logistic regression. Tying force was significantly associated with leakage (P < 0.001). Leakage was eliminated only at 14 N for both materials, whereas high leakage rates occurred at lower force levels regardless of suture material. Time interval and suture material were not independently associated with leakage. These findings indicate that ligation security in this model is determined primarily by tying force rather than by filament configuration.
Journal of biomedical materials research. Part AYifan Wu, Minghao Xu, Xixi Wang, Chijia Wang, Zhihong Wang, Jing Liu
The high incidence of cardiovascular diseases has led to an increasing demand for small-diameter vascular grafts. Polycaprolactone (PCL) is a commonly used synthetic polymer material in the construction of vascular grafts. However, PCL alone has limited bioactivity, which may affect its blood-contacting and tissue responses when used in small-diameter vascular grafts. Fish swim bladder-derived extracellular matrix (FSB-ECM) contains bioactive components such as collagen and has been investigated as a cardiovascular biomaterial, although its mechanical properties are limited. In this study, fish swim bladder-derived dECM was incorporated into PCL by electrospinning to fabricate a series of small-diameter vascular grafts. The study first confirmed that dECM was successfully loaded onto PCL fibers and significantly improved the hydrophilicity and degradation performance of the material. Based on the in vitro and ex vivo evaluations, the 15% PCL-dECM (3:7) formulation was selected for further in vivo testing because it showed a favorable balance of mechanical properties and hemocompatibility, including low platelet activation. Subsequent in vivo evaluation in a rat abdominal artery implantation model demonstrated that this dECM-modified graft achieved a 100% patency rate. Furthermore, it exhibited significant anti-inflammatory effects and was conducive to the organized deposition of extracellular matrix components, such as collagen and elastic fibers. This work successfully developed a novel small-diameter vascular graft that possesses both excellent bioactivity and mechanical properties. Our findings offer a promising strategy and a solid experimental foundation, supporting the future clinical translation of small-diameter vascular grafts.
Journal of biomedical materials research. Part B, Applied biomaterialsGopal Agarwal, Leina Owens, Khadeejah Ahmed, Christine E Schmidt
Decellularized extracellular matrix-based scaffolds have gained significant attention for tissue regeneration applications. However, there is a limited understanding of how storage conditions influence the rheological and biological properties of decellularized matrix-based injectable formulations. This study investigates the effects of different storage conditions (4°C, -80°C, and freeze-dried) on the rheological properties of a decellularized porcine peripheral nerve-derived extracellular matrix hydrogel. Our results demonstrated that, compared to storage at 4°C, formulations stored at -80°C and freeze-dried maintained comparable gelation kinetics (complete gelation within 11 min), mechanical properties (storage modulus around 300-350 Pa), and shear-thinning behavior across multiple time-points (Days 0, 3, 7, and 14 for -80°C), similar to freshly prepared formulations at Day 0. Solution stored at 4°C demonstrated a decrease in mechanical stiffness of hydrogel with time, however their gelation kinetics remained similar to Day 0. The solutions stored at -80°C and resuspended freeze-dried solutions maintained their complex viscosity, while 4°C stored solutions had relatively low complex viscosity as compared to freshly digested solutions. Overall, our findings suggest that -80°C storage and freeze-drying are suitable approaches for preserving decellularized porcine peripheral nerve-derived extracellular matrix formulations. Given the translational potential of these injectable biomaterials, understanding the influence of storage conditions on rheological performance is critical for developing appropriate storage and shipping strategies.
Journal of biomedical materials research. Part AAmal Shabazz, Julia Fitlin, Henry Orozco-Contreras, Cassandra Nti, William Pieper Holeman, Stephen Farias, John P Fisher
The rapid growth of additive manufacturing technologies continues to drive the commercial development of standardized materials to streamline the process. Despite the growing range of available materials, few still achieve a balance between flexibility and biocompatibility. Here, we evaluated the cytotoxicity of Formlabs Biomed Elastic 50A, Biomed Flexible 80A, and Biomed Durable resin using normal human dermal fibroblasts and human mesenchymal stromal cells. The sol fraction of the crosslinked and uncrosslinked materials was measured to determine the amount of leachable components in the polymer network. Following ISO 10993-5 guidelines, cytotoxicity was evaluated through direct, indirect, or extract testing for 24 h. All three materials did not elicit a cytotoxic response when assessed through fluorescence imaging and LDH assay. In each test, cells showed similar viability as cells cultured with a known noncytotoxic control, polycaprolactone, and showed significantly higher viability compared to a cytotoxic control, a polyurethane film containing 0.1% zinc diethyldithiocarbamate (ZDEC). Post-processing parameters were shown to minimize the effects of cytotoxicity when post-treated with an isopropyl alcohol wash, UV post-curing, or ethanol sterilization. Overall, the Formlabs Biomed Elastic 50A, Biomed Flexible 80A, and Biomed Durable resins were shown to exhibit minimal cytotoxicity after printing and post-processing. Further, the presented findings can be adapted to standardize in vitro testing of a wide range of commercial photocurable resins for tissue-interfacing parts.
Journal of biomedical materials research. Part AParvin Mohammadi, Mina Habibizadeh, Zhila Izadi, Kamran Mansouri, Mahmoudreza Moradi
Urethral stricture remains a challenging clinical condition, particularly in patients with long or complex defects where suitable donor tissue is limited. Tissue engineering offers a promising alternative through the development of biomimetic scaffolds capable of restoring urethral structure and function. In this study, we fabricated a sandwich nanofibrous scaffold based on polyglycolic acid (PGA) and decellularized urethral extracellular matrix (uECM) using a sandwich design (uECM/PGA/uECM) and compared it with PGA and mix (PGA-uECM) scaffolds. Successful decellularization was confirmed by histological and molecular analyses, demonstrating effective removal of cellular components while preserving ECM architecture. Structural characterization revealed high porosity, enhanced hydrophilicity, favorable swelling behavior, and controlled degradation in ECM-containing scaffolds. The uECM/PGA/uECM construct exhibited superior mechanical strength while maintaining suitable elasticity for urethral applications. Biological evaluation showed significantly improved endothelial cell adhesion, cell viability, and migration in ECM-integrated scaffolds compared with PGA alone. In vivo implantation demonstrated excellent biocompatibility, absence of adverse inflammatory responses, and evident neovascularization. Overall, the sandwich uECM/PGA/uECM scaffold combines mechanical stability with bioactive functionality, highlighting its potential as a promising candidate for urethral tissue regeneration.
Journal of biomedical materials research. Part B, Applied biomaterialsRenjie Li, Dandan Wei, Xinyang Pan, Anbei Chen, Tao Liu, Fengya Jing, Xin Tan, Yuzhou Chen, Tianhang Su, Junsheng Li, Long Zhu, Zhigang Zhang, Tianzhu Zhang
Postoperative intra-abdominal adhesion remains a major limitation of intraperitoneal polypropylene (PP) mesh. We evaluated three poly(vinyl alcohol) (PVA)-coated PP meshes-PVA-PP, rapamycin-loaded liposome-decorated PVA-PP (RPM@LPS/PVA-PP), and the corresponding NaHCO3-containing formulation [RPM@LPS(NaHCO3)/PVA-PP]-in a four-month exploratory laparoscopic Bama miniature-pig study. Two pigs received all four formulations at anatomically separated, randomized abdominal-wall sites, yielding 12 implantation sites in total and three site-level observations per formulation. Gross adhesion, abdominal-wall tissue-mesh mechanics, histology, collagen composition, immunohistochemistry, and multiplex immunofluorescence were assessed. Unmodified PP produced dense visceral attachment at all three implantation sites (mean site-level adhesion score, 4.00), whereas the mean scores for PVA-PP, RPM@LPS/PVA-PP, and RPM@LPS(NaHCO3)/PVA-PP were 0.50, 0.33, and 0.17, respectively. Adhesion area showed the same descriptive ordering. Mean abdominal-wall tissue-mesh lap-shear and peel strengths were also lowest with RPM@LPS(NaHCO3)/PVA-PP (0.0091 MPa and 0.1766 N mm-1, respectively) compared with PP (0.0500 MPa and 0.7823 N mm-1), indicating reduced host-wall integration rather than direct mechanical confirmation of weaker visceral adhesion. Modified interfaces showed less dense fibrous tissue, lower total and Type I collagen, and a higher Type III collagen fraction. The mean Type I/Type III collagen ratio decreased from 15.38 for PP to 2.27 for RPM@LPS(NaHCO3)/PVA-PP. Lower IL-6-, TNF-α-, α-SMA-, CD31-, CD68-, and iNOS-associated signals, together with a higher CD206-positive/CD68-positive area ratio, accompanied these changes. These exploratory two-animal findings show a descriptive association between the use of PVA-coated PP meshes and reduced chronic visceral adhesion, while identifying host-wall integration as a necessary safety consideration.
Cell biology internationalPraveen Ramakrishnan, Nooruddin Thajuddin, S B Mohamed, Saranya Vinayagam, Lalitha Gnanasekaran, Shanmugapriya D, Rajaram Rajamohan, Abdulkadhar Mohamed Jalalu…
Bone fracture healing is a meticulously regulated process encompassing the inflammatory, reparative, and remodelling phases. Macrophages serve as pivotal coordinators within this cascade, with their polarisation from pro-inflammatory M1 to proregenerative M2 phenotypes, which play a crucial role in determining the repair outcome. Emerging evidence underscores the significant influence of mechanical cues such as strain, stiffness, vibration, and scaffold topography on macrophage behaviour, thereby linking mechanobiology with immunology. This review summarises the current knowledge on mechano-immunomodulation in fracture repair, emphasising how mechanotransduction pathways, including Piezo1, YAP/TAZ, and PI3K/AKT, affect macrophage polarisation and their interactions with mesenchymal stem cells, osteoblasts, and endothelial cells. This review examined biomaterial strategies that leverage mechanical properties ranging from ceramic scaffolds and calcium phosphate coatings to hydrogels and advanced magnetic/electrical interfaces to shape the osteoimmune niche. Translational perspectives highlight mechanobiologics, immunometabolic reprogramming, and personalised loading regimens as next-generation approaches for fracture care. The remaining challenges include context-dependent macrophage responses, limited bone-specific mechanosensing data, and the need for standardised models and regulatory-compliant biomaterials. Collectively, these insights establish mechano-immunomodulation as a promising paradigm for enhancing bone regeneration and addressing the limitations of the current fixation-centric therapies.
Journal of biomedical materials research. Part ABryson White, Susmita Bose
This study investigates gooseberry (Phyllanthus emblica) extract (GB) as a bioactive additive to provide antibacterial activity and activity against osteosarcoma cells in hydroxyapatite-coated Ti6Al4V implants while maintaining osteoblast cytocompatibility. Aqueous extraction of GB yields a multicomponent formulation containing hydrophilic bioactive constituents that are prone to rapid release and poor retention under physiological conditions, thereby limiting their utility in implant-based delivery systems. To address this limitation, GB was encapsulated within liposomes to mitigate burst release and enable sustained delivery from implant surfaces. When incorporated onto plasma-sprayed hydroxyapatite-coated Ti6Al4V substrates, liposomal encapsulation reduced burst release within the first 48 h by 18% at pH 5.0 and 27% at pH 7.4. The formulation reduced osteosarcoma cell viability by 58% ± 7% after 11 days and decreased Pseudomonas aeruginosa and Staphylococcus aureus viability by 78% ± 3% and 45% ± 6%, respectively, within 48 h. Importantly, the system exhibited no cytotoxic effects toward osteoblasts, as demonstrated by MTT cell viability assays. In vivo evaluation of GB-treated implants after 6 weeks further demonstrated no adverse effect on early bone formation, with histological analysis showing a trend toward increased bone formation relative to control implants. These results demonstrate the feasibility of stabilizing and delivering a complex, hydrophilic natural extract from implant surfaces using liposomal encapsulation while maintaining osteoblast compatibility and without adversely affecting early bone formation in vivo.
Pathological retinal neovascularization (RNV) is a primary etiology of irreversible vision loss in debilitating conditions such as diabetic retinopathy and retinal vein occlusion. While metal-oxide nanomaterials have emerged as potent candidates for anti-angiogenic intervention, their clinical translation remains constrained by persistent biosafety concerns and inherent cytotoxicity. Manganese dioxide nanoparticles (MnO2NPs), distinguished by their robust enzyme-mimetic activity and microenvironment-responsive properties, have demonstrated substantial therapeutic promise in oncology; however, their specific function and underlying mechanisms in RNV remain largely uncharacterized. This study provides a systematic investigation into the anti-angiogenic potential of MnO2NPs and identifies molecular pathways that may underlie their activity, representing a step toward mechanistic proof-of-concept. Our results demonstrate that MnO2NPs possess exceptional biocompatibility bothin vitroandin vivo. These nanoparticles exert a potent, dose-dependent inhibitory effect on the proliferation, migration, and sprouting of human umbilical vein endothelial cells (HUVECs). Moving toin vivovalidation, MnO2NPs demonstrate a distinct capacity to modulate physiological retinal vascular development in neonatal mice and, more critically, markedly attenuate pathological neovascularization in an oxygen-induced retinopathy model. Mechanistically, integrated transcriptomic analysis revealed a significant modulation of angiogenesis-related gene clusters, which-along with Western blot validation-confirmed that MnO2NPs exert their effects by targeting the PLK1/AKT/FOXO1 signaling axis. In conclusion, MnO2NPs emerge as a compelling and innovative therapeutic candidate for managing vision-threatening ocular vascular disorders. These findings not only offer a targeted pharmacological intervention for retinal diseases but also provide a mechanistic blueprint for the rational design of next-generation multifunctional nanomedicines.
Journal of biomedical materials research. Part AAlex S Kermani, Andrea C Filler, J Kent Leach
Cultivated meat (CM) seeks to decouple meat production from animal agriculture, but producing structured products that consumers recognize as whole-cut meat remains both difficult and central to the field's ambitions. Scaffolds are key to this goal, providing architecture, cell-adhesion sites, and instructive cues required to organize cells into texturally mimetic tissue. To date, CM scaffold research has largely borrowed from tissue engineering, which optimizes for therapeutic function and does not account for the constraints that define a food product: edibility, low cost, and large scale. Here, we review scalable scaffold materials and fabrication methods for structured CM through this food-first lens. We identify relevant elements of the native muscle microenvironment and assess how these characteristics have been recapitulated. We then evaluate the major classes of scaffold materials, including those of synthetic, animal, plant, fungal, and microbial origin, as well as waste-stream-derived materials, and compare their biological suitability and scalability. We organize fabrication methods by the biological function they address: cell expansion, alignment, bulk structure, and multi-material assembly, treating mass transport as a constraint that cuts across these methods rather than a separate function. Throughout, we emphasize that consumer perception of meat quality is driven by architecture rather than physiological function, and throughput and cost determine commercial viability. We conclude by identifying critical gaps that warrant scientific focus to bring structured CM to market.
Biotechnology journalNiayesh Najafi, Kevin Babakhan Vartanian, Tony Eskandar, Edgmin Rostomian, Finosh G Thankam
PURPOSE: Adhesive hydrogels (AHs) are promising biomaterials for cardiac tissue engineering due to their injectability, ability to adhere to wet tissue, and structural similarity to the native extracellular matrix (ECM). This review evaluates the perspectives, opportunities, and challenges associated with AHs in cardiac tissue repair and functional recovery. Adhesion is achieved through chemical mechanisms including Schiff base reactions, Michael addition, and enzymatic crosslinking, as well as physical interactions including hydrogen bonding, host-guest complexation, and catechol-based binding. These mechanisms support integration with the dynamic and mechanically active cardiac surface ensuring the localized and sustained delivery of cells/therapeutics. METHODS: Peer reviewed articles were identified through searches of PubMed and Embase using terms related to "adhesive hydrogels," "bioadhesion," and "cardiac tissue engineering." Studies were included based on relevance to adhesion chemistry, mechanical integration, in vivo cardiac performance, and translational outcomes. RESULTS: Recent reports demonstrated improvements in ventricular remodeling, neovascularization, and scar size reduction, while early-stage clinical trials report safety and potential functional benefits of AH-based cardiac applications. CONCLUSION: Continued progress in material design, biocompatibility, and clinical delivery approaches is essential for translating adhesive hydrogels into routine therapies for heart management.
Biomedical physics & engineering expressAamir Shehzad, Wang Yanen, Ghulam Hassan Askari, Sidra Aslam, Nasar Ali
Porous orthopedic implants are widely studied because they promote osseointegration and reduce stress shielding associated with dense, stiff implants. This review critically examines recent progress in the design and fabrication of additively manufactured porous orthopedic implants, with a focused emphasis on polylactic acid (PLA)-bioceramic systems, particularly hydroxyapatite-, tricalcium phosphate-, and bioactive glass-containing composites. We examine how porosity governs biological outcomes-cell attachment and proliferation, nutrient transport, and bone ingrowth-while simultaneously affecting stiffness, strength, and fatigue resistance. Rather than treating pore size, porosity, and material selection as universally optimal parameters, the review emphasizes that these variables must be interpreted according to implant location, loading environment, degradation profile, and the expected timeline of bone repair. Key structural variables, including pore size, morphology, interconnectivity, and graded architectures, are discussed in the context of meeting load-bearing requirements. Particular attention is given to balancing permeability with mechanical integrity, and to approaches such as ceramic-filled PLA composites and surface modifications that improve bioactivity. Additive manufacturing is presented as an enabling route to couple external geometry with internal architecture, and fused deposition modeling, Stereolithography, and binder jetting are compared with respect to material compatibility, attainable feature resolution, and post-processing needs. Building on these insights, we frame co-design as the joint optimization of material selection and porous structure to maximize overall implant function. Finally, we identify the main barriers to clinical translation, including degradation-healing mismatch, fatigue durability, sterilization, reproducibility of porous architectures, regulatory documentation, and the need for long-termin vivovalidation.
Journal of materials chemistry. BShuo Chen, Xinlin Liu, Huitao Qi, Dan Wang, Qian Kong, Zhijuan Ai, Shuya Liang, Zhongmin Geng
A revolutionary development in biomaterial science, intracellular gelation technology allows for the in situ creation of three-dimensional polymer networks inside the cytoplasm to create an "artificial cytoskeleton". The cellular physicochemical microenvironment can be precisely manipulated using this method. In contrast to traditional biomaterials that function externally, intracellular gelation uses an "inside-out" approach to directly alter cellular states. The design principles, biological effects, and biomedical applications of mechanism-responsive hydrogel materials are highlighted in this review, which methodically summarizes recent advancements in the field worldwide. Even with all of its transformative capabilities, the area still encounters many limitations, such as safety concerns regarding the use of artificial cytoskeletons in the long run, poor efficacy of gelation heterogeneously in the single cell, and the absence of any in vivo targeted technique. This review provides a comprehensive overview of intracellular gelation technology, covering triggering mechanisms, material systems, biological effects, biomedical applications, and future perspectives.
Journal of the American Heart AssociationChristos Rammos, Olga Petrikhovich, Berna Akan, Medina Sacirovic, Julia Lortz, Sara Fakea, Ramtin Knuschke, Daniel Messiha, Tienush Rassaf
BACKGROUND: Drug-coated balloon treatment is the recommended strategy for endovascular peripheral artery disease treatment. Besides proliferation and migration of smooth muscle cells, endothelial dysfunction and inflammation are known contributors in the restenosis process. Sirolimus and paclitaxel are both antirestenotic agents, exerting different pharmacomechanic properties. METHODS: We investigated the differential effects of sirolimus- and paclitaxel-coated balloons (SCBs and PCBs, respectively) in the endovascular treatment of severe PAD on endothelial function and inflammation. Clinical outcomes were also assessed. LIMUS FLOW Trial (Sirolimus Versus Paclitaxel Drug-Coated Ballons for Femoropopliteal Disease: The LIMUS FLOW Randomized Trial) was a proof-of-concept investigator-initiated randomized controlled trial with 70 patients randomized to SCBs or PCBs. Endothelial function restoration was assessed via endothelial-dependent vasomotion measured by flow mediated dilatation of the superficial femoral artery. Inflammatory markers, perfusion, primary patency, and target lesion revascularization were evaluated. RESULTS: At 12 months, SCBs led to a greater improvement in endothelial function compared with PCBs (40% improvement with SCBs versus 22% with PCBs, P=0.023). The improvement in endothelial function was associated with reduced inflammatory markers following sirolimus application at 1-month follow-up. No differences were observed for primary patency or freedom from target lesion revascularization between the groups after 12 months. CONCLUSIONS: LIMUS FLOW explores a novel concept to achieve a more profound mechanistic understanding of vasomotion restoration after application of drug-coated balloons. Improved endothelial function restoration through 12 months, reduction of inflammatory markers through 30 days, with no difference in clinical outcomes, were observed following SCBs versus PCBs. REGISTRATION: URL: www.clinicaltrials.gov; Unique identifier: NCT05450042.
Plastic and reconstructive surgeryNeil Tanna, Isabelle T Smith, Evan Rothchild, Gabrielle Odoom, Ben H Zhang
LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Describe the types, structural characteristics, and clinical indications for biologic matrices and synthetic meshes used in breast aesthetic and reconstructive surgery. 2. Evaluate the evidence on clinical outcomes, complication profiles, and aesthetic results associated with each material. 3. Apply key principles of material selection based on patient-specific factors, procedural context, and surgical goals. SUMMARY: This article reviews the role of biologic matrices and synthetic meshes in breast aesthetic and reconstructive surgery. It discusses material composition, surgical applications, and emerging roles in aesthetic operations such as augmentation, mastopexy, and reduction. The authors compare complication rates, capsular contracture prevention, and aesthetic outcomes associated with each material type, highlighting differences in safety, cost-effectiveness, and long-term performance. Evidence-based data are presented to guide decision-making and improve patient outcomes, while acknowledging current limitations in the literature and opportunities for further investigation.
Bone researchDong Zhang, Laiqiang Tong, Lijie Mao, Dong Han, Fangping Chen, Changsheng Liu
Bone hemorrhage presents serious clinical challenges due to its high morbidity and mortality. Autologous coagulation forms blood clots that both halt bleeding and provide a natural scaffold for bone repair. The dynamic formation and dissolution of blood clots maintain a delicate balance between hemostasis and regeneration. Clot architecture and cytokine composition play pivotal roles in directing bone repair. These insights inspire biomimetic strategies using engineered biomaterials to regulate clot behavior, a central theme in designing bone-replacement systems that integrate hemostasis with osteogenesis. This review highlights the processes of clot formation following bone trauma and the contribution of cytokine-mediated signaling to bone repair. Particular emphasis is placed on how biomaterial implants modulate clot function via their physicochemical properties, such as chemical composition, structural characteristics, hydrophilicity, and surface charge. Additionally, the review examines the role of the clots during the early stages of bone injury and discusses the rational design principles for materials aimed at optimizing coagulation control and osteogenesis. Overall, this review reframes the clot not as a passive by-product of trauma but as an interface through which biomaterials seamlessly merge hemostasis and osteogenesis, offering a roadmap for multifunctional bone-replacement systems that halt bleeding while programming robust bone repair.
Biomaterials advancesLanbo Shen, Jiahao Yu, Tingting Kong, Xin Huang, Bin Li, William W Yu
Myocardial infarction (MI) causes irreversible cardiomyocyte loss and adverse ventricular remodeling, yet current cardiac patches remain limited by inadequate bioactivity and poor electrical integration with host myocardium. We report a multifunctional metal-phenolic conducting polymer hydrogel (CPH) for post-infarction myocardial repair. A one-pot process integrates a conductive polypyrrole network with dynamic Cu2+-tannic acid (TA) coordination, thereby combining electrical conductivity, mechanical support, and redox-related functionality within a single hydrogel. Cu-TA CPH exhibited myocardium-matched mechanical properties (∼19 kPa), suitable conductivity, good biocompatibility, and intrinsic antioxidant and antibacterial activities. These combined features enabled the hydrogel patch to provide mechanical support, facilitate electrical communication, and improve the local microenvironment after MI. On postoperative day 7, left ventricular ejection fraction in the Cu-TA CPH-treated MI group was higher than that in the MI group receiving no material treatment. This therapeutic effect was associated with an increased Bcl-2/Bax ratio, enhanced VEGFR-1 expression, reduced infarct size, and improved myocardial tissue preservation. Collectively, Cu-TA CPH represents a promising hydrogel patch for post-infarction myocardial repair.
The Chinese journal of dental researchGuang Yan Yu
Bone, a dynamic and complex tissue, possesses limited regenerative potential, which poses formidable challenges in orthopaedic surgery and clinical dentistry. In particular, for large bone defects beyond critical size, compromised physiological conditions due to comorbidities (i.e. osteoporosis and type 2 diabetes) or severe trauma, its intrinsic healing capacity often falls short, necessitating advanced therapeutic interventions. For decades, research on bone regeneration has predominantly focused on biomaterial design, growth factor delivery and cell-based therapies. More recently, a paradigm shift has occurred, recognising the critical role of the bioelectric microenvironment in orchestrating bone homeostasis and repair. At the forefront of this exciting field, the pioneering work of Professor Xuliang Deng and colleagues at Peking University School of Stomatology has systematically elucidated the intricate interplay between electrical signalling cues and bone regeneration, paving the way for novel electroactive biomaterial strategies. These are summarised by the accompanying review article,1 which is published in this issue of the Chinese Journal of Dental Research.
BACKGROUND: The management of acute oral hemorrhage in emergency settings is frequently complicated by saliva, high vascularity, and microbial presence. This scoping review maps the emerging field of multifunctional, dental-inspired biomaterials. The objective is to synthesize evidence on injectable materials providing rapid hemostasis and antimicrobial protection, while acknowledging the current transition from laboratory models to clinical applications. METHODS: Following PRISMA-ScR guidelines and the Population-Concept-Context (PCC) model, we searched Scopus, PubMed, and Web of Science (updated search date: July 10, 2026). No language restrictions were applied. Two authors independently performed screening and data extraction (Cohen's Kappa = 0.88). Review articles provided thematic context, while 13 primary research studies provided data for performance benchmarking. No formal protocol was registered. RESULTS: Analysis of 13 primary studies reveals a shift toward chitosan and gelatin-methacryloyl (GelMA) matrices. Quantitative synthesis showed a 32%-42% reduction in hemostasis time compared with commercial controls [1, 2], primarily in low-pressure models. Antimicrobial zones of inhibition ranged from 10 to 18 mm. Antimicrobial action was primarily validated against planktonic, single-species cultures, with effectiveness against complex oral biofilms yet to be proven. CONCLUSIONS: Current evidence supports the application of these materials for minor-to-moderate hemorrhage. Broad application for major arterial trauma remains a future objective requiring longitudinal safety studies on nanoparticle bioaccumulation and dynamic mechanical validation under arterial pressure.
The pronounced heterogeneity of the pathological microenvironment in musculoskeletal disorders poses significant challenges to the spatiotemporal regulation capabilities of conventional therapeutic strategies. Stimuli-responsive hydrogels have exhibited immense potential for the treatment of musculoskeletal disorders owing to their excellent intelligent response characteristics and versatile design. This review systematically summarizes the major response mechanisms of stimuli-responsive hydrogels and analyzes the characteristics of their structural and functional design. It further focuses on recent advances of their applications in typical musculoskeletal disorders, including degenerative diseases such as osteoarthritis (OA); autoimmune diseases such as rheumatoid arthritis (RA); traumatic injuries such as fractures and cartilage injury; infectious diseases such as infected bone defects; metabolism-related bone disorders such as diabetic bone injury and hyperlipidemia bone injury; as well as soft tissue complications such as tendon adhesion and rotator cuff injury. Finally, this review proposes a design concept for multimodal stimuli-responsive hydrogels and discusses the key challenges in their clinical translation. We hope this review will serve as a reference for promoting the treatment of musculoskeletal disorders from passive repair to active regulation.
Journal of applied oral science : revista FOBStephanie Isabel Diaz Zamalloa, Caroline Carvalho Dos Santos, Leticia Martins Santos, Victor Elias Arana-Chavez, Fernando Neves Nogueira, Carla Renata Sipert, …
INTRODUCTION: The unpredictability of blood clots as natural scaffolds in regenerative endodontic procedures (REPs) has driven the search for synthetic alternatives with reproducible properties. This study aimed to develop and characterize a dual-scale micro/nanofibrous poly(lactic-co-glycolic acid) (PLGA) scaffold fabricated by co-electrospinning and evaluate its physicochemical and biological suitability for REPs under lipopolysaccharide (LPS)-induced inflammatory conditions. METHODOLOGY: A 7.5% (w/v) PLGA solution was co-electrospun using distinct parameters (flow rate and needle-to-collector distance) to generate a dual-scale fiber architecture. Physicochemical characterization included water uptake, in vitro degradation, and morphological analysis by scanning electron microscopy (SEM). Biological properties were evaluated using human apical papilla cells (APCs). Metabolic activity (Alamar Blue), mineralization (Alizarin Red S), and cell adhesion/morphology (SEM) were assessed in the presence or absence of LPS to simulate an inflammatory environment. RESULTS: The co-electrospun scaffold showed a hierarchical structure with interconnected micro and nanofibers. Water uptake reached 147.4% within 24 h and increased gradually thereafter. The scaffold showed a biphasic degradation profile-slow initial degradation (21.5% over 28 days) followed by accelerated loss (63.1% at day 45). Hydration induced fiber swelling and pore remodeling. The scaffold supported APC adhesion, spreading, and metabolic activity over 72 h. Under LPS stimulation, APCs maintained metabolic activity and showed robust mineralization potential after 21 days, comparable to the positive control. CONCLUSION: The co-electrospun PLGA scaffold showed physicochemical properties compatible with tissue ingrowth and supported APCs function under inflammatory conditions. By providing a controlled microenvironment, it represents a potential scaffold design for future REPs.
Acta of bioengineering and biomechanicsMałgorzata Żak, Sylwia Szotek, Klaudia Szkoda-Poliszuk, Krzysztof Kołtowski, Piotr Menartowicz, Celina Pezowicz
PURPOSE: Growth-guidance spinal systems are used in children with progressive spinal deformity to reduce repeated surgical lengthening while allowing continued spinal growth. Their long-term biomechanical behaviour under cyclic loading remains insufficiently characterised. This study assessed whether diamond-like carbon (DLC) coating of rods and sliding screws affects axial stiffness and local kinematics in a growth-guidance spinal system. METHODS: Twelve porcine Th11-L7 spine specimens were assigned to three groups: non-instrumented control, non-coated titanium alloy instrumentation, and instrumentation with DLC-coated components. Specimens underwent 100,000 cycles of axial compression. Axial stiffness was evaluated after 100 and 100,000 cycles. Vertebral range of motion from Th12 to L6 was measured using rigid body markers, and local rod-screw interface displacements were assessed using three-dimensional digital image correlation. RESULTS: Stiffness increased similarly in all groups up to approximately 80,000 cycles. After 100,000 cycles, construct stiffness was approximately 6% lower in DLC coated instrumentation than in non-coated titanium alloy instrumentation. In the coated construct, segmental mobility at Th12-L1 and L5-L6 remained closer to the non-instrumented condition, whereas non-coated titanium alloy instrumentation showed reduced motion at these levels. Digital image correlation demonstrated time-dependent differences in local rod-screw interface kinematics between coated and non-coated constructs. CONCLUSION: DLC coating did not increase overall construct stiffness during cyclic axial compression, but it modified local mechanical behaviour and was associated with preservation of segmental mobility at selected levels. Further studies should determine whether these effects are maintained under multi-axis loading and in long-term tribological conditions.
Cell-laden three-dimensional (3D) bioprinted hydrogels have emerged as a promising technique for enhanced wound healing by integrating biomaterials, living cells, and precise fabrication technology. Chronic wounds that persist for an extended period of time, especially when pathologically affected by diseases like diabetes, can pose a serious threat to patients' health. Conventional dressing materials typically fail to provide adequate mechanical strength, drug release control, and complete tissue regeneration. In contrast, 3D bioprinting can allow for the selective deposition of cells into the extracellular matrix-mimetic hydrogels, making it possible to construct biomimetic scaffolds for tissue regeneration. This review provides a clear overview of how key cellular components such as mesenchymal stem cells, adipose-derived stem cells (ADSCs), fibroblasts, and multicellular systems contribute to important wound healing processes like immunomodulation, angiogenesis, cell proliferation, and re-epithelialisation. It also explores how bioprinting factors, including bioink rheology, cross-linking methods, and processing conditions, influence printability, the structural stability of scaffolds, and cell survival. The close relationship between scaffold design and how cells respond is emphasised as a key factor in determining how effective the treatment will be. Although pre-clinical studies have shown promising results, bringing this research into real-world clinical use remains challenging due to issues like lack of standardisation, difficulties in scaling up, regulatory hurdles, and high costs.
BMC oral healthAlaa A Salem, Mohamed S Hammed, Ahmed M ElRawdy, Hesham ElHawary
BACKGROUND: Whether grafting peri-implant jumping gaps exceeding 2 mm during immediate implant placement improves outcomes remains uncertain. This trial evaluated the effect of β-tricalcium phosphate (β-TCP) grafting on implant stability and peri-implant radiodensity in such sites. METHODS: In this prospective, parallel-group randomized controlled trial, 16 patients (8 per group) receiving 39 immediate maxillary anterior/premolar implants at sites with a jumping gap exceeding 2 mm were randomized 1:1 to no grafting (control) or injectable β-TCP (test); the patient was the unit of analysis. The pre-specified primary comparison was implant stability quotient (ISQ) at 6 months. Peri-implant radiodensity was monitored on standardized periapical radiographs (grayscale value) at baseline, 3, and 6 months, and quantified by cone-beam CT (CBCT) at 6 months only (ALARA principle); CBCT values are relative, arbitrary gray-value radiodensity, not true Hounsfield units. Between-group differences were analyzed with independent-samples t tests, within-group changes with repeated-measures ANOVA, and group×time interactions with mixed-design ANOVA (α = 0.05). RESULTS: No statistically significant between-group differences were detected in baseline age or jumping-gap width. No significant between-group difference in ISQ was detected at any time point, and the ISQ group×time interaction was not significant (p = 0.49); ISQ increased significantly over time in both groups. Periapical grayscale value increased significantly faster in the test group on unadjusted analysis (group×time interaction, p = 0.009), but this was no longer significant after adjusting for a small baseline difference (ANCOVA, p = 0.39). On 6-month CBCT, radiodensity was significantly higher in the test group (1224.0 ± 237.0) than control (931.9 ± 100.4 arbitrary units; mean difference 292.1; 95% CI 87.7 to 496.5; p = 0.010), a secondary outcome not included in the a priori sample-size calculation. CONCLUSIONS: β-TCP grafting of jumping gaps exceeding 2 mm did not significantly affect ISQ or baseline-adjusted periapical grayscale value. The test group showed significantly higher 6-month CBCT-derived radiodensity, but this was not prospectively powered and may partly reflect residual graft material, so it should be interpreted cautiously. Larger, adequately powered equivalence trials are needed before conclusions about grafting necessity can be drawn. TRIAL REGISTRATION: ClinicalTrials.gov, NCT07709676. Registered 2026-07-12. Retrospectively registered.
Traumatic blood loss is a key issue in emergency medicine and wound management. Developing materials that can both quickly inhibit bleeding and properly treat wounds is of great significance. Traditional hemostatic materials are widely used in clinical settings, but they still have limitations in terms of adaptability to irregular wounds, limited stability in wet environments, single functionality, and difficulty in balancing subsequent therapy. In recent years, self-gelling powders have attracted considerable interest owing to their translational advantages, including convenient storage, portability, and ease of application, as well as their capacity to undergo rapid in situ gelation upon contact with blood or tissue exudate. These materials can not only achieve rapid hemostasis through liquid absorption concentration, physical filling, promoting blood cell aggregation, and enhancing wound sealing, but also improve the wound microenvironment through moisturizing, antibacterial, anti-inflammatory, antioxidant, and promoting angiogenesis pathways, thereby facilitating tissue repair. This review establishes a mechanistic taxonomy of powder-to-gel transformation based on dominant network-forming interactions and discusses the structure-property-performance relationships governing gelation kinetics, wet adhesion, mechanical stability, and biological outcomes. Representative applications in non-compressible hemorrhage, wet tissue sealing, infected/chronic wounds, and specialized anatomical sites are systematically summarized. Furthermore, a critical analysis of the key transformation challenges in the future was conducted, and future design principles for next-generation self-gelling wound materials are proposed.
Zhonghua shao shang yu chuang mian xiu fu za zhiL F Cui, J Jin, H W Wu
Objective: To prepare a lecithin liposome-tea tree essential oil-polyhexamethylene biguanide hydrochloride complex (Lip-TTO-PHMB) and to investigate its in vitro antibacterial activity and biocompatibility. Methods: This study was an experimental research including group design, factorial design, and repeated measurement design. Lip-TTO-PHMB was prepared by the thin-film hydration method. Through single-factor experiments combined with the Box-Behnken response surface methodology, the optimal preparation condition for Lip-TTO-PHMB was determined as follows: mass ratio of egg yolk lecithin to cholesterol of 3.77:1.00, volume fraction of tea tree essential oil of 0.64%, and volume fraction of polysorbate 80 of 0.13%. The model-predicted encapsulation efficiency was 51.035%. Lip-TTO-PHMB was prepared under the optimal preparation condition and its encapsulation efficiency was measured by ultracentrifugation ultraviolet method. Mouse fibroblasts L929 were divided into lecithin liposome-polyhexamethylene biguanide hydrochloride (Lip-PHMB) group treated with Lip-PHMB, Lip-TTO-PHMB group treated with Lip-TTO-PHMB, and polyhexamethylene biguanide hydrochloride (PHMB) group treated with PHMB, with the final mass concentrations of PHMB adjusted to 62.5, 31.3, and 15.6 μg/mL, and the cell viability was detected by the thiazolyl blue assay after 24 h of culture. Another batch of L929 cells were divided into the same groups as before and treated with the corresponding materials with the final mass concentration of PHMB at 15.0 μg/mL, and the cell viability was detected by live/dead cell staining after 24 h of culture. The sample size for the above experiments was 4. Human immortalized keratinocytes (HaCaTs) were divided into control group cultured with serum-free MEM medium, PHMB group treated with PHMB, and Lip-TTO-PHMB group treated with Lip-TTO-PHMB, with the final mass concentration of PHMB at 15.0 μg/mL. The scratch test was performed to detect the cell migration rates at 24 and 48 h after scratch (with the sample size of 3). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of PHMB in three materials against Staphylococcus aureus ATCC 6538 and Escherichia coli ATCC 8739 were determined by the broth microdilution twofold dilution method, with the sample size of 5. Results: The measured encapsulation efficiency of Lip-TTO-PHMB was (52.35±0.24)%, which was close to the model-predicted value. The results detected by thiazolyl blue assay showed that after 24 h of culture, at PHMB final mass concentrations of 62.5, 31.3, and 15.6 μg/mL, the viability of L929 cells in Lip-PHMB group and Lip-TTO-PHMB group was significantly higher than that in PHMB group (P<0.05), and the viability of L929 cells in Lip-PHMB group was significantly higher than that in Lip-TTO-PHMB group (P<0.05). The results detected by live/dead cell staining showed that after 24 h of culture, the viability of L929 cells in PHMB group was significantly lower than that in Lip-PHMB group and Lip-TTO-PHMB group (with P values both <0.05). At 24 and 48 h after scratch, the migration rates of HaCaT cells in Lip-TTO-PHMB group were significantly higher than those in PHMB group (P<0.05); at 48 h after scratch, the migration rate of HaCaT cells in control group was significantly higher than that in PHMB group (P<0.05). The MICs of Lip-PHMB, Lip-TTO-PHMB, and PHMB against Staphylococcus aureus were 31.3, 15.6, and 15.6 μg/mL, respectively, and those against Escherichia coli were 31.3, 15.6, and 7.8 μg/mL, respectively. The MBCs of Lip-PHMB, Lip-TTO-PHMB, and PHMB against Staphylococcus aureus were 20, 10, and 15 μg/mL, respectively, and those against Escherichia coli were 30, 20, and 20 μg/mL, respectively. Conclusions: The Lip-TTO-PHMB is prepared successfully, and the material possesses excellent antibacterial activity while retaining favorable biocompatibility.
Biomaterials advancesPeter Trosan, Franziska Frost, Jessica Hoerner, Jana Schaetzel, Thomas Eickner, Marcus Himmler, Susanne Staehlke, Volkmar Senz, Andreas Götz, Niels Grabow, Sab…
Descemet's Membrane Endothelial Keratoplasty (DMEK) is one of the most common therapies to re-establish visual acuity caused by corneal endothelial cell loss. Donor tissue shortages become increasingly relevant. Therefore, the main objective of this study was the evaluation of potential fiber substitute materials suitable for DMEK. Six electrospun biomaterials (three degradable: poly-l-lactide (PLLA), PLLA plus lecithin and tetraethylammonium chloride (PLLA+), polydioxanone (PDO); three non-degradable: polyurethanes (TSPEU, TSPCU), thermoplastic elastomer (TPC-ET) were examined regarding their structure, transparency, cell viability, metabolic cell activity, and endothelial phenotypic markers. Cell behavior was assessed on plasma-activated as well as on non-activated biomaterials to distinguish a possible influence of cold plasma activation. All biomaterials were suitable scaffolds for endothelial cells (HCEC) in varying degrees. No significant differences could be found between plasma-activated and non-activated scaffolds. PLLA+ ranked highest in total cell number. All biomaterials were comparable regarding cell toxicity, with high levels of cell viability. qPCR analysis revealed higher expression of genes responsible for HCEC's proliferation and morphology cultured on TSPEU, PLLA, and PLLA+. In summary, PLLA and PLLA+ showed the highest number of cells with high viability and cell proliferation whilst preserving their phenotype. In addition, PLLA and PLLA+ ranked highest in light transmission, which makes them promising candidates as artificial DMEK replacements.
Biomaterials advancesAnabela Veiga, João B Costa, Viviana P Ribeiro, Glenn Leung, David L Kaplan, Ana L Oliveira
Three-dimensional (3D) bioprinting requires inks and bioinks that combine appropriate processing and mechanical properties with a biologically supportive environment capable of sustaining cell viability and proliferation. Silk-based biomaterials have attracted considerable attention in biofabrication due to their tunable properties, processability, and structural similarity to extracellular matrix components. While most silk-based inks/bioinks rely primarily on silk fibroin (SF) for structural integrity, the use of silk sericin (SS) as a cell-supportive component remains comparatively underexplored in bioprinting. As a hydrophilic protein, SS has been associated with favorable cell responses, including cell adhesion and proliferation. Additionally, SS has been reported to support cell growth in culture media, or to replace fetal bovine serum (FBS). These characteristics have motivated the exploration of sericin in formulations intended for cell encapsulation Furthermore, as a by-product of the silk industry, SS is a sustainable protein source, providing an environmental dimension to its biomedical use. In the current study, we combined both silk proteins to develop a proof-of-concept bilayer silk-based printed construct. SS-based hydrogels were formulated with gelatin and glycerol to encapsulate human dermal fibroblasts (HDFs), while SF-based ink was incorporated into the 3D printing process as a structurally supportive biomaterial. The inks/bioinks were processed using extrusion-based 3D bioprinting and subsequently crosslinked through an enzymatic horseradish peroxidase/hydrogen peroxide (HRP/H₂O₂) system to stabilize the hydrogel network. These structures supported HDF viability and proliferation under the tested in vitro conditions. Overall, these results highlight the potential of silk proteins as a proof-of-concept 3D bioprinting platform that combines a SF-based structural support ink with a sericin-containing cell-laden bioink in which HDF viability and proliferation were supported under the tested in vitro conditions.
Biomaterials advancesAnita Puspitasari, Thi Kim Ngan Duong, Anky Fitrian Wibowo, Vu Hoang Minh Doan, Truong Tien Vo, Jaeyeop Choi, Yong Hyun Kim, Jae Sung Ahn, Sudip Mondal, Junghw…
Artificial intelligence (AI), especially machine learning (ML) and deep learning (DL), is rapidly changing biomaterials science. These computational tools enable researchers to analyze large and complex datasets, discover new materials, and improve the design and performance of existing ones. ML and DL algorithms learn from experimental and simulation data to predict material properties, guide synthesis, and optimize manufacturing conditions, often faster than conventional trial-and-error approaches. In recent years, AI-based methods have been applied across biomaterials research, including predicting the biocompatibility and mechanical strength of new materials, improving additive manufacturing (AM) processes, and enhancing the precision of biofabrication and tissue engineering. AI tools are increasingly applied to real-time quality assessment and adaptive control during material production, enabling the design of "smart" biomaterials that respond dynamically to environmental and biological signals, with potential uses in regenerative medicine, healthcare devices, and sustainable materials. This emerging field still faces key challenges, such as the difficulty of obtaining large and reliable datasets needed to train accurate AI models. Another critical issue is the interpretability of complex ML and DL models. Understanding why an algorithm makes a certain prediction is essential for building trust and guiding experimental validation. To address these issues, researchers are turning to explainable AI (XAI) approaches that provide greater transparency and insight into model behavior. This review summarizes recent progress in applying ML, DL, and XAI to biomaterials science. It also highlights the main opportunities and challenges for developing intelligent, real-time adaptive materials for healthcare, regenerative medicine, and sustainable material design.
Biomedical physics & engineering expressQichen Sun, Siti Noor Fazliah Mohd Noor, Siti Fatimah Samsurrijal, Nawal Radhiah Abdul Rahman
Bioactive glasses (BGs) are widely used in various fields of dentistry, and reinforcing these BGs with fluoride is of particular interest for the remineralisation of dental hard tissue. In this study, fluoride-reinforced 50S8P BGs (BGF and mBGF) were prepared using the sol-gel method at different ageing temperatures. The BGs were manually ground into powder, sieved and characterised using thermogravimetric analysis (TGA) and differential scanning calorimetry ( (TGA-DSC), X-ray diffraction (XRD), X-ray Fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS). The fluoride-reinforced BG (BGF and mBGF) exhibited a greater mass loss based on TGA, whilst DSC analysis showed that the addition of fluoride reduced transition temperature, crystallisation temperature and melting temperature. XRD analysis revealed that fluoride incorporation led to the formation of Na2Ca2Si3O9and fluorinated phases such as Ca5(PO4)3F, NaCa2FSiO4and CaSiO2F2. FTIR spectra indicated that fluorine (F) in the composition bonded with Si-O-Si (tetrahedral structure) functional groups. XRF and EDS results confirmed the presence of fluorine in BG and mBGF samples, with a higher fluoride content observed in the mBGF sample. After incubation in simulated body fluid, XRD, FTIR and SEM analyses demonstrated that all three samples (BG, BGF and mBGF) were capable of forming a hydroxyapatite layer. Furthermore, BGF and mBGF exhibited the formation of fluoroapatite, indicating enhanced remineralisation potential. Additionally, these BGs showed non-toxicity at low doses and were biocompatible with SaOS-2 cells based on MTT assay results.
Journal of orthopaedics and traumatology : official journal of the Italian Society of Orthopaedics and TraumatologyGiovanni Vicenti, Filippo Migliorini, Michele Loiodice, Alessandro Scarpino, Priscilla D'attis, Luise Schäfer, Giulia Colasuonno, Giuseppe Solarino
BACKGROUND: Fracture-related infection (FRI) is a devastating complication of intramedullary nailing of tibial and femoral diaphyseal fractures. The present study evaluates the clinical efficacy of an antibacterially coated intramedullary nail in patients with high-risk tibial and femoral diaphyseal fractures. Open fractures, fractures requiring fasciotomy or closed fractures with Tscherne grade II or III soft-tissue damage were considered fractures at high risk of infection. METHODS: A single-centre observational study was conducted between January 2022 and December 2024, in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. Patients who underwent definitive intramedullary nailing with Bactiguard (Bactiguard AB, Tullinge, Sweden)-coated Natural Nail (Zimmer Biomet, Warsaw, IN, USA) for tibial or femoral diaphyseal fractures at high risk of infection were included. The primary outcome was the incidence of FRI, defined according to the internationally validated consensus criteria. Secondary outcomes included time to union, rates of nonunion, malunion, unplanned secondary procedures and functional outcomes at a minimum follow-up of 12 months. RESULTS: A total of 103 patients were enrolled: 55 with tibial fractures and 48 with femoral fractures. The combined cohort comprised 90 males and 13 females, with a median age of 40 years (tibial) and 32.5 years (femoral). Open fractures accounted for 38.2% and 16.7% of tibial and femoral cases, respectively; the remaining patients presented closed fractures with severe soft-tissue involvement (Tscherne grade II-III). FRI was diagnosed in 6 of 103 patients (5.8%): 4 of 55 in the tibial cohort (7.3%) and 2 of 48 in the femoral cohort (4.2%). All FRI cases were successfully managed without sepsis or limb amputation. Fracture union was achieved in 94.5% of tibial and 95.8% of femoral cases, with mean times to union of 9.8 ± 3.2 and 8.4 ± 2.3 months, respectively. No malunion was recorded in either cohort. Open reduction was significantly associated with FRI in both the tibial (p = 0.001) and femoral (p = 0.03) cohorts; articular extension of the fracture was associated with FRI in femoral fractures (p = 0.01). CONCLUSIONS: Intramedullary nailing with a Bactiguard-coated implant yielded an overall FRI rate of 5.8% in a consecutive series of 103 high-risk tibial and femoral diaphyseal fractures. Open reduction was identified as a significant independent risk factor for FRI in both cohorts. These findings are hypothesis-generating and support the rationale for prospective, controlled studies to establish the efficacy of biofilm-inhibiting coatings in orthopaedic trauma.