Journal of biomedical materials research. Part B, Applied biomaterials最新文献

This study investigates the structural, morphological, hydrodynamic, colloidal stability, anticancer, antibacterial, antioxidant, and hemolytic properties of Cu and Mn doped ZnS nanosheets (NSs). XRD examination indicated that the produced NSs exhibit high purity with a cubic structure. The average crystallite size was determined to be 1.66 nm for ZCMn1, 1.60 nm for ZCMn2, 1.26 nm for ZCMn3, and 1.39 nm for ZCMn4 NSs (ZnS = ZCMn1; Zn_0.98Cu_0.02S = ZCMn2; Zn_0.97Mn_0.01Cu_0.02S = ZCMn3; Zn_0.96Mn_0.02Cu_0.02S = ZCMn4). TEM analysis showed that the synthesized NSs exhibit a crumpled nanosheet morphology with agglomerated particles. The ZCMn4 NSs displayed the smallest hydrodynamic size and the best colloidal stability. The ZCMn4 NSs also demonstrated superior antibacterial efficacy, with zones of inhibition (ZOI) measuring 14mm, 14 mm, 17 mm, 16 mm, and 13 mm for S. aureus, E. faecalis, P. aeruginosa, E. coli, and C. albicans, respectively. Antioxidant and hemolytic activities were also evaluated, further highlighting the multifunctionality of the synthesized nanomaterials. Notably, the ZCMn4 NSs exhibited minimal hemolytic activity, with a lysis rate of only 0.33% at a dosage of 500 μg/mL. The doped and dual-doped ZnS NSs exhibited strong and selective cytotoxic effects against melanoma cells while sparing normal melanocytes. Furthermore, a TUNEL assay was performed to confirm that the reduction in cell viability resulted from apoptotic cell death. These findings underscore the potential of Mn and Cu-doped ZnS nanosheets as promising therapeutic nanomaterials for cancer treatment, drug delivery, MRI, and other biological applications.

Polyanhydride particle-based vaccines overcome several limitations of current vaccines owing to their ability to encapsulate different types of antigenic payloads, provide tunable release kinetics of payloads, and induce protective immunity against multiple respiratory infections. In this work, two particle synthesis methods were compared by analyzing the structure and antigenicity of released proteins from particles made by these methods. Flash nanoprecipitation is a lab-scale method to synthesize protein-loaded particles. Spray drying is a scalable method that allows for the production of protein-loaded particles. The polyanhydride copolymer used for both synthesis methods was composed of a 20:80 M ratio of 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane and 1,6-bis(p-carboxyphenoxy)hexane. The three proteins used in this work are bovine serum albumin (a model, globular protein), and SARS-CoV-2 spike and bovine RSV post-F protein (both clinically relevant proteins). The release kinetics of the encapsulated proteins were studied, and the structure of the released proteins was analyzed using gel electrophoresis and fluorescence spectroscopy. The antigenicity of the released spike and post-F was estimated based on the binding of positive mouse sera from previously inoculated mice. Our results indicate that both flash nanoprecipitation and spray drying resulted in particle formulations that provided a burst release of protein followed by a sustained period of release. The primary and tertiary structures and the antigenicity of the released proteins were maintained consistently across both methods. Altogether, these studies indicate that spray drying can be used to generate particles that stabilize encapsulated antigens and for at-scale particle synthesis in the future.

The promising outcome of Bone Tissue Engineering (BTE) via scaffolds for treating segmental bone defects (SBDs) has led the interdisciplinary field of Materials Science to take a new turn and explore innovative biomaterials that enhance tissue regeneration. The most recent advancement is the application of electrical stimulation with the use of conductive and piezoelectric biomaterials to develop conductive and electroactive (EA) scaffolds that activate osteoblast formation, leading to a significantly faster and more robust bone healing process. Researchers have explored plenty of biomaterials and scaffold fabrication techniques. This article presents a comprehensive review of the popular biomaterials that include Conductive Polymers (PANI, Poly-pyrrole, PEDOT), Piezoelectric Polymers (PVDF, TrFE, PLLA, PAs), Metallic Nanoparticles (NPs) (Ag, TiO₂), and Carbon-based NPs (CNTs, Graphene, Graphene Oxide) used for the development of conductive and EA biocompatible scaffolds. Various innovative conductive and electroactive scaffold fabricating methods, like 3D printing, bio-printing, electrospinning, etc., that precisely command over the conductive filler distribution, porosity, and pore size interconnectivity are highlighted. Tests explored by researchers for investigating the conductive and piezoelectric properties of the developed scaffolds and their osteogenic potential (in vitro and in vivo) are also presented. Apart from this, standard protocols for the conduction of these tests, regulatory pathways, scope for clinical translations, and their respective challenges have been reviewed. Most importantly, the review not only focuses on the material versatility and fabrication techniques but also critically analyzes the challenges involved in optimizing the biomaterials and fabrication parameters to develop bone scaffolds with the best-optimized physicochemical, mechanical, biological, and conductive properties.

Osteoarthritis (OA) is a degenerative joint disease characterized by cartilage breakdown and chronic inflammation. Current therapies mainly relieve symptoms but do not halt disease progression. We developed collagen hydrogels incorporating propolis-loaded zeolitic imidazolate framework-8 (ZIF-8) nanoparticles (PROZIF) and menstrual blood-derived stem cells (MenSCs). In vitro assays evaluated microstructure, cell viability, anti-inflammatory activity, drug release, and cytoprotection. An osteoarthritis model was induced in rats by monosodium iodoacetate (MIA). Animals received intra-articular injections of hydrogels, and outcomes were assessed by histology, enzyme-linked immunosorbent assay (ELISA), knee swelling, and locomotor function. Collagen–PROZIF–MenSCs hydrogels with 2% nanoparticle content (COL-PROZIF-MenSCs-2) preserved MenSC viability, showed strong anti-inflammatory effects, and provided sustained propolis release. In vivo, this group significantly reduced cartilage degeneration, decreased tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β), and increased transforming growth factor-beta (TGF-β) and fibroblast growth factor (FGF) levels compared to controls. Knee swelling was reduced, and locomotor scores improved. Combining ZIF-8 nanoparticles with MenSCs in collagen hydrogels synergistically mitigated OA progression in rats by reducing inflammation and supporting cartilage repair. This approach demonstrates promise as a localized, cell- and drug-based therapy for OA, warranting further long-term and translational studies.

Suture selection influences wound healing, patient comfort, and infection risk in implant surgery. Although monofilament sutures are commonly recommended for implant surgery, the comparative clinical performance of different types of monofilament sutures remains underexplored. This study compared the clinical and microbiological performance of polyamide and polytetrafluoroethylene (PTFE) sutures. A split-mouth design was used in 19 patients (38 implant sites) to compare wound healing, patient comfort, and bacterial adherence associated with polyamide and PTFE sutures. Wound healing was assessed using the early wound healing score (EHS, 0–10 scale), patient comfort via a visual analog scale (VAS, 1–10), and bacterial colonization using real-time quantitative PCR (qPCR) analysis of seven oral pathogens. Knot retention was recorded on days 0 and 7. Mean early wound healing scores were similar between PTFE (6.47 ± 0.52) and polyamide (6.63 ± 0.63) (p > 0.05). No significant differences were found between the two groups regarding surrounding tissue irritation (p > 0.05). However, knot stability decreased significantly for both materials, with polyamide showing higher knot loss (44.4% vs. 22.2%, p = 0.008). A significant number of Porphyromonas gingivalis were detected in PTFE compared to polyamide, which demonstrated enhanced reepithelialization and minimal tissue reaction. Both suture types achieved satisfactory healing and patient comfort, but their distinct microbial adhesion patterns may influence long-term peri-implant outcomes. Polyamide demonstrated lower P. gingivalis colonization and better re-epithelialization, suggesting potential clinical advantages.

Microgels are increasingly recognized as versatile building blocks for granular cell scaffolds, offering advantages over bulk hydrogels for a variety of biomedical applications. While existing methods for scaffold fabrication often require multistep processes involving separate microgel formation and assembly, here we introduce a streamlined, one-pot approach that achieves microgel formation and scaffold assembly in minutes. This developed method is robust, reproducible, user-friendly, and requires no specialized equipment, making it broadly accessible. Specifically, aqueous two-phase separation (ATPS) was utilized to form ~2 μm gelatin methacrylate (GelMA) microgels in sodium sulfate salt solution, which rapidly “clicked” to form macroporous scaffolds under UV light. Various parameters were modulated to observe the effect on scaffold formation including timing of UV exposure, salt concentration, photoinitiator concentration, and polymer concentration. Our results indicated a mechanically stable scaffold able to quickly imbibe water due to its interconnected macropores. U-87 glioblastoma, NIH 3T3 fibroblast, and ATDC5 chondrocyte cells were successfully encapsulated within these granular scaffolds and exhibited an elongated morphology at 24 h and > 90% viability over 14–21 days of culture. The ability to produce microgel scaffolds containing living cells in one step opens new routes to the production of cell-laden porous scaffolds.