Mesoporous Bioactive Glass Nanoparticles Research Articles

3D Bioprinting of Multifunctional Dynamic Nanocomposite Bioinks Incorporating Cu-Doped Mesoporous Bioactive Glass Nanoparticles for Bone Tissue Engineering.

Bioprinting has seen significant progress in recent years for the fabrication of bionic tissues with high complexity. However, it remains challenging to develop cell-laden bioinks exhibiting superior physiochemical properties and bio-functionality. In this study, a multifunctional nanocomposite bioink is developed based on amine-functionalized copper (Cu)-doped mesoporous bioactive glass nanoparticles (ACuMBGNs) and a hydrogel formulation relying on dynamic covalent chemistry composed of alginate dialdehyde (oxidized alginate) and gelatin, with favorable rheological properties, improved shape fidelity, and structural stability for extrusion-based bioprinting. The reversible dynamic microenvironment in combination with the impact of cell-adhesive ligands introduced by aminated particles enables the rapid spreading (within 3 days) and high survival (>90%) of embedded human osteosarcoma cells and immortalized mouse bone marrow-derived stroma cells. Osteogenic differentiation of primary mouse bone marrow stromal stem cells (BMSCs) and angiogenesis are promoted in the bioprinted alginate dialdehyde-gelatin (ADA-GEL or AG)-ACuMBGN scaffolds without additional growth factors in vitro, which is likely due to ion stimulation from the incorporated nanoparticles and possibly due to cell mechanosensing in the dynamic matrix. In conclusion, it is envisioned that these nanocomposite bioinks can serve as promising platforms for bioprinting complex 3D matrix environments providing superior physiochemical and biological performance for bone tissue engineering.

Homology of selenium (Se) and tellurium (Te) endow the functional similarity of Se-doped and Te-doped mesoporous bioactive glass nanoparticles in bone tissue engineering

The focus of bone tissue engineering is to realize the regeneration of new functional bone through the synergistic combination of biomaterials, therapeutic agents and cells. Doping of mesoporous bioactive glass (MBG) nanoparticles with therapeutic ions to give them special properties is gaining increasing interest in the design of biomaterials for bone tissue engineering. In this study, we synthesized Se-doped and Te-doped MBG nanoparticles using the sol-gel method, and demonstrated for the first time that the homology of Se and Te endows the functional similarity of bone tissue engineering, and also obtains the desired properties by guiding cell behavior and changing the physicochemical properties of the biomaterial. Results found that MBG nanoparticles doped with Se and Te respectively can be gained similar structure, and thus endowed their similar properties as expected, such as drug sustained release, anticancer and antibacterial properties in a dose-dependent manner. This study provides a feasible strategy for the development of homologous group ions doped nanobiomaterials and their evaluation and basic research in bone tissue engineering. Highlights • Homology of Se and Te endow the functional similarity of Se-doped and Te-doped MBGs. • Se doped MBGs exhibited excellent antibacterial activity on S. aureus (92.54%). • Te doped MBGs exhibited controllable DOX release in vitro. • Se-doped and Te-doped MBGs all exhibited high anti-bone cancer activity in vitro.

Cerium-Containing Bioactive Glasses Promote In Vitro Lymphangiogenesis.

The lymphatic system is crucial for the regeneration of many tissues due to its fundamental role in immune cell trafficking, protein transport, and tissue homeostasis maintenance. Strategies stimulating lymphangiogenesis can provide new therapeutic approaches for tissue repair and regeneration (e.g., chronic wound healing). Here, we explored the effects of cerium-containing mesoporous bioactive glass nanoparticles (Ce-MBGNs) on lymphangiogenesis. The results showed that the extracts of Ce-MBGNs (1, 5, or 10 wt/v%) were non-cytotoxic toward lymphatic endothelial cells (LECs), while they enhanced the proliferation of LECs. Moreover, as evidenced by the scratch wound healing and Transwell migration assays, conditioned media containing the extract of Ce-MBGNs (1 wt/v%) could enhance the migration of LECs in comparison to the blank control and the media containing vascular endothelial growth factor-C (VEGF-C, 50 ng/mL). Additionally, a tube-formation assay using LECs showed that the extract of Ce-MBGNs (1 wt/v%) promoted lymphatic vascular network formation. Western blot results suggested that Ce-MBGNs could induce lymphangiogenesis probably through the HIF-1α/VEGFR-3 pathway. Our study for the first time showed the effects of Ce-MBGNs on stimulating lymphangiogenesis in vitro, highlighting the potential of Ce-MBGNs for wound healing.

Boswellia sacra Extract-Loaded Mesoporous Bioactive Glass Nano Particles: Synthesis and Biological Effects

Bioactive glasses (BGs) are being increasingly considered for numerous biomedical applications. The loading of natural compounds onto BGs to increase the BG biological activity is receiving increasing attention. However, achieving efficient loading of phytotherapeutic compounds onto the surface of bioactive glass is challenging. The present work aimed to prepare novel amino-functionalized mesoporous bioactive glass nanoparticles (MBGNs) loaded with the phytotherapeutic agent Boswellia sacra extract. The prepared amino-functionalized MBGNs showed suitable loading capacity and releasing time. MBGNs (nominal composition: 58 wt% SiO2, 37 wt% CaO, 5 wt% P2O5) were prepared by sol-gel-modified co-precipitation method and were successfully surface-modified by using 3-aminopropyltriethoxysilane (APTES). In order to evaluate MBGNs loaded with Boswellia sacra, morphological analysis, biological studies, physico-chemical and release studies were performed. The successful functionalization and loading of the natural compound were confirmed with FTIR, zeta-potential measurements and UV-Vis spectroscopy, respectively. Structural and morphological evaluation of MBGNs was done by XRD, SEM and BET analyses, whereas the chemical analysis of the plant extract was done using GC/MS technique. The functionalized MBGNs showed high loading capacity as compared to non-functionalized MBGNs. The release studies revealed that Boswellia sacra molecules were released via controlled diffusion and led to antibacterial effects against S. aureus (Gram-positive) bacteria. Results of cell culture studies using human osteoblastic-like cells (MG-63) indicated better cell viability of the Boswellia sacra-loaded MBGNs as compared to the unloaded MBGNs. Therefore, the strategy of combining the properties of MBGNs with the therapeutic effects of Boswellia sacra represents a novel, convenient step towards the development of phytotherapeutic-loaded antibacterial, inorganic materials to improve tissue healing and regeneration.

Local delivery of naringin in beta-cyclodextrin modified mesoporous bioactive glass promotes bone regeneration: from anti-inflammatory to synergistic osteogenesis and osteoclastogenesis.

The bone immune response dominated by macrophages plays an indispensable role in the osteogenesis of bone defects. Moreover, moderate polarization of macrophages against inflammatory M2 has been proved to promote osteogenesis. Therefore, the addition of anti-inflammatory agents to bioactive bone repair materials facilitates efficient bone regeneration by regulating the polarization of macrophages. Bioactive glass (BG) has been widely used for bone defect repair. However, BG alone cannot effectively inhibit the inflammatory response caused by in vivo biomaterial implantation, and finally cannot achieve satisfactory bone repair effect. Herein, the design of mesoporous bioactive glass nanoparticles (MBG) modified with β-cyclodextrin (CD-MBG) is reported. Our research shows that the anti-inflammatory drug naringin (NG) is loaded into CD-MBG (NG@CD-MBG), which achieves a sustained release within 6 days. In vitro studies reveal that NG@CD-MBG promotes better transformation of macrophages to the M2 phenotype than MBG inhibiting macrophage inflammatory responses, while the induced local immune microenvironment synergistically facilitates osteogenesis and inhibits osteoclastogenesis. Furthermore, in vivo high expression of osteogenesis-related genes in the microenvironment stimulated by NG@CD-MBG significantly promotes new bone formation in the femoral defect model of rats. The results indicate that the combination of MBG and NG has a synergistic effect on immunomodulating osteogenesis and osteoclastogenesis, providing a novel idea for the development of bone biomaterials with favorable bone immunomodulatory properties.

Fabrication of Lithium and Cobalt Co-Doped Mesoporous Bioactive Glass Nanoparticles for in Vitro Angiogenesis and Osteogenesis

Fabrication of Lithium and Cobalt Co-Doped Mesoporous Bioactive Glass Nanoparticles for in Vitro Angiogenesis and Osteogenesis

Tendon-bone junction healing by injectable bioactive thermo-sensitive hydrogel based on inspiration of tendon-derived stem cells

The rotator cuff repaired construct must establish a contiguous and functioning tendon-bone junction to provide adequate stability. However, fibrocartilage deficiency and bone loss were hardly reversed after physical suture, especially in chronic rotator cuff tears. In this study, we synthesized an injectable methylcellulose/polyvinyl alcohol/polyvinylpyrrolidone-based thermo-sensitive hydrogel, which delivered kartogenin-loaded mesoporous bioactive glass nanoparticles. Physicochemical studies the revealed phase transition temperatures of 35 °C and its ability to induce chondrogenesis and osteogenesis differentiation of tendon-derived stem cells. Furthermore, experiments in rabbit chronic rotator cuff tears model confirmed the fibrocartilage and bone layer regenerative capability of the injected bioactive hydrogel, which could, in turn, support the ultimate tensile stress of the repaired rotator cuff. The bioactive agents-loaded hydrogel reported in this study is a valuable addition to the arsenal of biomaterials in applications to chronic tendon-bone junction injuries.

Incorporation of Zinc into Binary SiO2-CaO Mesoporous Bioactive Glass Nanoparticles Enhances Anti-Inflammatory and Osteogenic Activities.

During the healing and repair of bone defects, uncontrolled inflammatory responses can compromise bone regeneration. Biomaterials with anti-inflammatory activity are favorable for bone tissue regeneration processes. In this work, multifunctional Zn-containing mesoporous bioactive glass nanoparticles (Zn-MBGs) exhibiting favorable osteogenic and anti-inflammatory activities were produced employing a sol-gel method. Zn-MBGs exhibited a mesoporous spherical shape and nanoscale particle size (100 ± 20 nm). They were degradable in cell culture medium, and could release Si, Ca, and Zn in a sustained manner. Zn-MBGs also exhibited a concentration-dependent cellular response. The extract of Zn-MBGs obtained by incubation at 0.1 mg/mL (in culture medium) for 24 h could enhance in vitro mineralization, alkaline phosphatase activity, the expression of osteogenesis-related genes, and the production of intracellular protein osteocalcin of rat bone marrow stromal cells (BMSCs). Moreover, the extract of Zn-MBGs at 0.1 mg/mL could significantly downregulate the expression of inflammatory genes and the production of inducible nitric oxide in RAW 264.7 cells, particularly under stimulation of inflammatory signals interferon-γ (IFN-γ) and lipopolysaccharide (LPS). Zn-MBGs also inhibited the pro-inflammatory M1 polarization of RAW264.7 cells induced by LPS and IFN-γ. In summary, we successfully synthesized Zn-MBGs with concentration-dependent osteogenic and anti-inflammatory activities. Zn-MBGs show their great potential in immunomodulation strategies for bone regeneration, representing a multifunctional biomaterial that can be applied to regenerate bone defects under inflammatory conditions.

Construction of tellurium-doped mesoporous bioactive glass nanoparticles for bone cancer therapy by promoting ROS-mediated apoptosis and antibacterial activity

The commonly used treatment methods for bone cancer include chemotherapy, surgery and radiotherapy, but there are disadvantages such as nonspecific distribution, high toxicity of chemotherapy drugs, implantable infections and low monitoring. Nanoparticles are the new development direction of nanomedicine in cancer treatment. Structural characteristics of nanoparticles make it an excellent model for targeting and penetrating cancer-induced abnormal cell growth. In this study, a kind of novel and interesting tellurium ion doped mesoporous bioactive glasses (Te-MBG) nanoparticles were successfully synthesized by a simple sol–gel method, which had uniform spherical morphology (≈ 500 nm), high surface area (> 300 m2/g) and mesopore volume (> 0.30 cm3/g). Results found that Te doping does not affect the mineralization and degradation of the MBG nanoparticles. Meanwhile, compared to the undoped MBG, Te doped MBG not merely had the ability to promote MG63 cell apoptosis to inhibit bone cancer growth by ROS-mediated, but also had significant antibacterial activity. This all depends on the concentration of Te doping. It can be seen that Te-MBG nanoparticles can not only potentially fill bone defects caused by bone cancer removal, but also induce cancer cell apoptosis by tellurium release inducing reactive oxygen species (ROS) excessive production to inhibit bone cancer formation. This study provides a feasible strategy for the development of Te-MBG nanoparticles as well as their evaluation and basic research for bone cancer therapy.

Enhanced antimicrobial and remineralizing properties of self-adhesive orthodontic resin containing mesoporous bioactive glass and zwitterionic material

Background/purposeSelf-adhesive resins (SARs) do not require additional restorative adhesives and provide adequate adhesion to mineralized dental structures by shortening the bonding time in clinics where moisture control and isolation are difficult. The aim of this study was to evaluate the mechanical and biological properties of SARs containing mesoporous bioactive glass nanoparticles (MBNs) and 2-methacryloyloxyethyl phosphorylcholine (MPC) and to determine their antibacterial and remineralization effects.Materials and methodsMBNs and MPC were added to SARs to improve their physical properties and remineralization ability. The experimental resins assessed in this study were SARs mixed with 3%MPC, 5%MPC, 1%MBN+3%MPC, or 3%MBN+3%MPC. The shear bond strength, microhardness, adhesive remnant index, ion dissolution, degree of conversion, and antibacterial properties of the SARs were evaluated. To assess the remineralization properties, micro-computed tomography analysis was performed after pH cycling.ResultsIncreasing the MBN content in SAR resulted in higher microhardness compared to the control SAR. The shear bond strength decreased in the SAR+5%MPC group and increased in the SAR+1%MBN+3%MPC and SAR+3%MBN+5%MPC groups.ConclusionOur findings suggest that SARs containing MBNs and MPC have antibacterial and remineralization effects on the enamel.

Anti-inflammatory and antibacterial activities of cerium-containing mesoporous bioactive glass nanoparticles for drug-free biomedical applications.

Mesoporous bioactive glass nanoparticles (MBGNPs) are attracting significant attention as suitable materials for multifunctional biomedical applications. In this study, cerium was incorporated into MBGNPs using two different approaches. In the first approach, cerium was added to the glass system directly during the synthesis, while in the second approach, cerium was added to the as-synthesized MBGNPs via the template ion-exchange method. The influence of the method of synthesis on the physicochemical properties of nanoparticles was examined by SEM, TEM, XRD, FTIR, and N2 adsorption-desorption analyses. The MBGNPs exhibited spheroidal morphology and disordered mesoporous structure. XRD analysis confirmed the amorphous nature of the nanoparticles. The chemical composition was determined by the acid digestion method using ICP-OES. The influence of the synthesis method on the specific surface area, mesoporosity, and solubility of synthesized nanoparticles in Tris/HCl (pH 7.4) and acetate (pH 4.5) buffer has also been studied. The obtained Ce containing MBGNPs were non-cytotoxic toward ​preosteoblast MC3T3-E1 cells in contact with nanoparticles in a concentration of up to 100 ​μg/mL. The anti-inflammatory effect of Ce containing MBGNPs was tested with lipopolysaccharides (LPS)-induced proinflammatory RAW 264.7 macrophage cells. Ce containing MBGNPs decreased the release of nitric oxide, indicating the anti-inflammatory response of macrophage cells. Ce containing MBGNPs also showed antibacterial activity against S. aureus and E. coli. The mentioned features of the obtained MBGNPs make them useful in a variety of biomedical applications, considering their biocompatibility, anti-inflammatory response, and enhanced antibacterial effect.

Biodegradable dual-crosslinked adhesive glue for fixation and promotion of osteogenesis

The effective fixation of fracture fragments is the foundation for the smooth healing process of fracture. Due to the presence of small fracture fragments, the comminuted fracture cannot be fixed under high mechanical strength leading to the bone nonunion and delayed healing. In this study, the primary crosslinked injectable bone glue was fabricated by the Schiff base reaction between low substitution degree methacrylate gelatin (GelMa) and Oxidized dextran (oDex) covalently crosslinked with Aminated mesoporous bioactive glass nanoparticles (AMBGN), then the second crosslinked bone glue was formed among small fracture fragments after the irradiation. By this method, the osteogenic dual-crosslinking biodegradable bone glue was synthesized with enhanced mechanical capability. This bone glue was biocompatible and biodegradable, in addition, after the second crosslinking, the mechanical strength was 2.1 times higher than that in primary cross-linking. Moreover, the dual-crosslinked bone glue also exhibited excellent adhesion ability on the isolated rat bone tissues. Additionally, the bone glue can increase the proliferation of bone marrow mesenchymal stem cells (BMSCs) and enhance the expression of Alkaline phosphatase (ALP) and the deposition of calcium nodules with the up-regulating expression of the osteogenic protein (Runx2) and adhesin (Vinculin) in vitro. Furthermore, the bone glue also presented enhanced osteogenesis in the rat calvarial critical-size defect models in vivo. Overall, this osteogenic dual-crosslinking biodegradable bone glue with high mechanical strength provided a new approach in treating the comminuted fracture fragments.

Fabrication of bone-targeting hyaluronic acid coupled alendronate-bioactive glass for osteosarcoma therapy

Osteosarcoma is a complicated clinical cancer for patients, which seriously reduces the quality of life. The current conventional treatment is focused on controlling cancer cell proliferation and osteoclast activity. The aim is to develop mesoporous bioactive glass (MBG) with bone-targeting hyaluronic acid-alendronate (HA-ALN) components for osteosarcoma treatment. The prepared MBG was enclosed by the HA-ALN to form mesoporous bioactive glass nanocomposites (MBGNCs) and characterized surface functionalization, size, shape, and morphology. MBG nanoparticles were spherical and smooth surfaces; after coating with HA-ALN they exhibited a stable structure with changes in the surface textures. Bisphosphonate coupled HA controls the swelling under physiological conditions by preventing rapid degradation of the nanocomposites. It also confirms the drug release, which shows a maximum of 65% DOX release at pH 4.5. Drug release studies confirm the pH variation was slightly altered in the DOX release ratio due to the HA-ALN. It also helps in higher binding ability on the hydroxyapatite components, indicating the bone targeting ability and nanocomposites. ALN components actively inhibit osteoclast-like cells. MBGNCs witnessed the higher toxicity to the osteosarcoma cancer cells of IC50 value of 4 μg/mL. MBGNCs inhibitory effects on the viability of the MG-63 osteosarcoma cancer cells were higher compared to free DOX. The bone targeting effect of HA-ALN coated MBGNCs shows higher cellular uptake, which helps inhibit tumor growth and helps in the long term of bone tissue regeneration. MBGNCs highly followed the bone targeting, pH-dependent drug release contributed to the treatment of bone metastasis and promoted osteoblast differentiation.

Polymer (PCL) fibers with Zn‐doped mesoporous bioactive glass nanoparticles for tissue regeneration

AbstractComposite fibrous membranes based on poly(ɛ‐caprolactone) (PCL) and mesoporous bioactive glass nanoparticles (MBGNs) were fabricated by electrospinning. MBGNs and Zn‐doped MBGNs prepared by microemulsion sol–gel method were successfully incorporated inside the polymeric fibers of 240 and 385 nm in diameter for undoped and Zn‐doped PCL_MBGNs fibers, respectively. Thermal analysis showed that the concentration of MBGNs reached a maximum of around 21 wt% for Zn‐doped MBGNs. Both PCL_MBGNs and PCL_MBGNs_Zn composite membrane exhibited bioactivity after immersion in simulated body fluid (SBF). X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) showed the evolution of composite membranes, confirming the formation of hydroxyapatite (HAp). However, the degradation products of membranes did not affect the viability and proliferation of murine stromal cells (ST‐2) and thus the new fiber structures represent a suitable environment for cell adhesion. Therefore, the incorporation of mesoporous glass nanoparticles doped with therapeutically active Zn2+ ions inside the PCL fibers offers the possibility to create a multifunctional biomaterial suitable for drug delivery and tissue engineering.

Combination of Selective Etching and Impregnation toward Hollow Mesoporous Bioactive Glass Nanoparticles.

In this study, binary SiO2-CaO hollow mesoporous bioactive glass nanoparticles (HMBGNs) are prepared by combing selective etching and impregnation strategies. Spherical silica particles (SiO2 NPs) are used as hard cores to assemble cetyltrimethylammonium bromide (CTAB)/silica shells, which are later removed by selective etching to generate a hollow structure. After the removal of CTAB by calcination, the mesoporous shell of particles is formed. Calcium (Ca) is incorporated into the particles using impregnation by soaking the etched SiO2 NPs in calcium nitrate aqueous solution. The amount of incorporated Ca is tailorable by controlling the ratio of SiO2 NPs:calcium nitrate in the soaking solution. The produced HMBGNs are bioactive, as indicated by the rapid formation of hydroxyapatite on their surfaces after immersion in simulated body fluid. In a direct culture with MC3T3-E1 cells, HMBGNs were shown to exhibit concentration-dependent cytotoxicity and can stimulate osteogenic differentiation of MC3T3-E1 cells at concentrations of 1, 0.5, and 0.25 mg/mL. Our results indicate that the combination of selective etching and impregnation is a feasible approach to produce hierarchical HMBGNs. The produced hollow particles have potential in drug delivery and bone tissue regeneration applications, and should be further investigated in detailed in vitro and in vivo studies.

Flexible Osteogenic Glue as an All‐In‐One Solution to Assist Fracture Fixation and Healing

AbstractOsteogenic glue that reproduces the natural bone composition represents the final frontier of orthopedic adhesives with the potential to revolutionize surgical strategies against comminuted fractures. However, it is difficult to achieve an all‐in‐one formula, which could provide flexible and reliable adhesiveness while avoiding interfering with or even promoting the healing of glued fractures. Herein, an osteogenic glue characterized by inorganic‐in‐organic integration between amine‐modified mesoporous bioactive glass nanoparticles (AMBGN) and bioadhesive gelatin‐dextran network (GelDex) is introduced as an all‐in‐one tool to flexibly adhere and splice bone fragments and subsequently guide fracture healing during degradation. Relying on such integration, a 4‐fold improvement in cohesiveness is presented, followed by a nearly 5‐fold enhancement in adhesive strength in ex vivo porcine bone samples. The reversible and re‐adjustable adhesiveness also enables glue to effectively splice intricate fragments from highly comminuted fractures in the rabbit radius in an in vivo environment. Moreover, well‐preserved organic–inorganic integrity during degradation of the glue guides sustained interfacial osteogenesis and achieve satisfying healing outcomes in glued fractures, as observed by the 2‐fold improvement in biomechanical and radiological performance compared with commercially available cyanoacrylate adhesives. The current findings propose an all‐in‐one solution for the fixation of bone fragments during surgery.

Anti-Microbial and Remineralizing Properties of Self-Adhesive Orthodontic Resin Containing Mesoporous Bioactive Glass.

Self-adhesive resins (SARs) contain adhesives, which simplify the procedures of resin application, and primers, which provide sufficient bonding ability. In this study, mesoporous bioactive glass nanoparticles (MBN) were added to a SAR to easily improve the physical properties and remineralization ability. The experimental resins comprised 1%, 3%, and 5% MBN mixed in Ortho Connect Flow (GC Corp, Tokyo, Japan). As the MBN content in the SAR increased, the microhardness increased, and a statistically significant difference was observed between the cases of 1% and 5% MBN addition. Shear bond strength increased for 1% and 3% MBN samples and decreased for 5% MBN. The addition of MBN indicated a statistically significant antibacterial effect on both gram-negative and gram-positive bacteria. The anti-demineralization experiment showed that the remineralization length increased with the MBN content of the sample. Through the above results, we found that SAR containing MBN has antibacterial and remineralization effects. Thus, by adding MBN to the SAR, we investigated the possibility of orthodontic resin development, wherein the strength is enhanced and the drawbacks of the conventional SAR addressed.

Fabrication and Characterization of Cinnamaldehyde-Loaded Mesoporous Bioactive Glass Nanoparticles/PHBV-Based Microspheres for Preventing Bacterial Infection and Promoting Bone Tissue Regeneration.

Polyhydroxybutyrate-co-hydroxyvalerate (PHBV) is considered a suitable polymer for drug delivery systems and bone tissue engineering due to its biocompatibility and biodegradability. However, the lack of bioactivity and antibacterial activity hinders its biomedical applications. In this study, mesoporous bioactive glass nanoparticles (MBGN) were incorporated into PHBV to enhance its bioactivity, while cinnamaldehyde (CIN) was loaded in MBGN to introduce antimicrobial activity. The blank (PHBV/MBGN) and the CIN-loaded microspheres (PHBV/MBGN/CIN5, PHBV/MBGN/CIN10, and PHBV/MBGN/CIN20) were fabricated by emulsion solvent extraction/evaporation method. The average particle size and zeta potential of all samples were investigated, as well as the morphology of all samples evaluated by scanning electron microscopy. PHBV/MBGN/CIN5, PHBV/MBGN/CIN10, and PHBV/MBGN/CIN20 significantly exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli in the first 3 h, while CIN releasing behavior was observed up to 7 d. Human osteosarcoma cell (MG-63) proliferation and attachment were noticed after 24 h cell culture, demonstrating no adverse effects due to the presence of microspheres. Additionally, the rapid formation of hydroxyapatite on the composite microspheres after immersion in simulated body fluid (SBF) during 7 d revealed the bioactivity of the composite microspheres. Our findings indicate that this system represents an alternative model for an antibacterial biomaterial for potential applications in bone tissue engineering.

Integration of Mesoporous Bioactive Glass Nanoparticles and Curcumin into PHBV Microspheres as Biocompatible Composite for Drug Delivery Applications.

Bioactive glasses (BGs) are being increasingly considered for biomedical applications. One convenient approach to utilize BGs in tissue engineering and drug delivery involves their combination with organic biomaterials in order to form composites with enhanced biocompatibility and biodegradability. In this work, mesoporous bioactive glass nanoparticles (MBGN) have been merged with polyhydroxyalkanoate microspheres with the purpose to develop drug carriers. The composite carriers (microspheres) were loaded with curcumin as a model drug. The toxicity and delivery rate of composite microspheres were tested in vitro, reaching a curcumin loading efficiency of over 90% and an improving of biocompatibility of different concentrations of MBGN due to its administrations through the composite. The composite microspheres were tested in terms of controlled release, biocompatibility and bioactivity. Our results demonstrate that the composite microspheres can be potentially used in biomedicine due to their dual effects: bioactivity (due to the presence of MBGN) and curcumin release capability.

Electrophoretically deposited high molecular weight chitosan/bioactive glass composite coatings on WE43 magnesium alloy

Abstract Mg-based materials are good candidates for biodegradable bone regeneration implants due to their favorable mechanical properties and an excellent compatibility with human bone. However, too high corrosion/degradation rate in body fluids still limits their applicability. Coatings based on chitosan (CS) and bioactive glass (BG) particles fabricated by electrophoretic deposition (EPD) on Dulbecco's Modified Eagle Medium (DMEM) pre-treated magnesium alloys have promising potential to suppress the substrate corrosion and additionally to incorporate bioactivity. However, the impact of processing parameters or type of coating components on the long-term substrate corrosion behavior and cell response have not been investigated previously. In this study, two types of composite coatings based on a high molecular weight CS (Mw 340–360 kDa, DDA ≥ 95%) and embedded particles: solid BG (2 μm) and a mixture of BG and mesoporous bioactive glass nanoparticles (MBGN, 100–300 nm with mesopores 2.3–5.6 nm) were fabricated by EPD on DMEM pre-treated WE43 magnesium alloy. It was found that partial replacement of BG particles with MBGN (ratio 3:1) in the composite coating increases the water contact angle, surface roughness and induces a positive cell response. Although the acidic CS-based solutions and applied EPD conditions may decrease the stability of the temporary barrier formed during the DMEM pre-treatment on WE43 substrate therewith slightly increasing its corrosion sensitivity, the composite coating with a mixture of different sizes of particles (BG, MBGN) is a promising candidate for bone regeneration applications.