CO-Mediated Alkali-Neutralization Curdlan Hydrogels for Potential Wound Healing Application.

Physical hydrogels of natural polysaccharides are considered as ideal candidates for wound dressing due to their natural biological activity and no harmful cross-linking agents. However, it remains a challenge to fabricate such hydrogel dressings in a facile and low-cost way. Herein, we reported an easy and cost-effective method to construct CO-mediated alkali-neutralization Curdlan (CR) hydrogels without using an external cross-linking agent.

3D printed strontium-zinc-phosphate bioceramic scaffolds with multiple biological functions for bone tissue regeneration.

Calcium phosphate (CaP) bioceramics are broadly employed for bone regeneration due to their excellent biocompatibility and osteoconductivity. However, they are not capable of repairing healing-impaired bone defects such as defects with conditions of ischemia or infection due to restricted bioactivities. In this study, we synthesized single-phased strontium-zinc-phosphate (SZP, SrZn(PO)) bioceramics a solution combustion method and further fabricated SZP scaffolds using a three-dimensional (3D) printing technique.

Mild Heat-Assisted Polydopamine/Alginate Hydrogel Containing Low-Dose Nanoselenium for Facilitating Infected Wound Healing.

In clinical practice, it has become urgent to develop multifunctional wound dressings that can combat infection and prompt wound healing simultaneously. In this study, we proposed a polydopamine/alginate/nanoselenium composite hydrogel (Alg-PDA-Se) for the treatment of infected wounds. In particular, polydopamine endows the composite hydrogel with controllable near-infrared photothermal properties, while low-dosage selenium nanoparticles (Se NPs) offer excellent anti-oxidation, anti-inflammatory, pro-proliferative, pro-migration, and pro-angiogenic performances, which are verified by multiple cells, including macrophages, fibroblasts, and endothelial cells.

Nanosized concave pit/convex dot microarray for immunomodulatory osteogenesis and angiogenesis.

The immunomodulatory capability of biomaterials is of paramount importance for successful material-mediated bone regeneration. Particularly, the design of surface nano-topography can be leveraged to instruct immune reactions, yet the understanding of such "nano-morphology effect" is still very limited. Herein, highly ordered nano-concave pit (denoted as NCPit) and nano-convex dot (denoted as NCDot) microarrays with two different sizes were successfully constructed on a 316LSS surface via anodization and subsequently immersion-coating treatment, respectively.

Construction of selenium-embedded mesoporous silica with improved antibacterial activity.

In this work, different concentrations of Se-incorporated mesoporous silica nanospheres (MSNs) (5Se/MSNs and 10Se/MSNs) were successfully synthesized via an in-situ one-pot method. Their physicochemical properties were characterized by X-ray diffraction (XRD), transmission electron microscopy, and X-ray photoelectron spectroscopy (XPS). The release behaviors of Se and Si were investigated in a phosphate-buffered saline (pH = 5.

Cytocompatibility and Bone-Formation Potential of Se-Coated 316L Stainless Steel with Nano-Pit Arrays.

316L stainless steel is still widely applied in joint replacement and orthopedic surgery due to its mechanical properties, corrosion resistance and relatively low price. In this study, electrochemical oxidation and nanoscale coating were used to fabricate Se-coated 316L stainless steel with nano-pit arrays to enhance its surface characteristics, biocompatibility and osseointegration ability. The modified 316L stainless steel was tested via field emission scanning microscopy (FESEM), energy-dispersive X-ray spectrometry (EDS), X-ray photoelectron spectroscopy (XPS) and Se release studies.

Nanoporous microstructures mediate osteogenesis by modulating the osteo-immune response of macrophages.

The osteoimmune environment plays indispensable roles in bone regeneration because the early immune environment that exists during the regenerative process promotes the recruitment and differentiation of osteoblastic lineage cells. The response of immune cells growing on nanotopographic surfaces and the microenvironment they generate should be considered when evaluating nanotopography-mediated osteogenesis, which are topics that are generally neglected in the field. In this study, we investigated the modulatory effects of nanoporous anodic alumina with different sized pores on macrophage responses and their subsequent effects on the osteogenic differentiation of bone marrow stromal cells (BMSCs).

Enhanced apatite-forming ability and antibacterial activity of porous anodic alumina embedded with CaO-SiO2-Ag2O bioactive materials.

In this study, to provide porous anodic alumina (PAA) with bioactivity and anti-bacterial properties, sol-gel derived bioactive CaO-SiO2-Ag2O materials were loaded onto and into PAA nano-pores (termed CaO-SiO2-Ag2O/PAA) by a sol-dipping method and subsequent calcination of the gel-glasses. The in vitro apatite-forming ability of the CaO-SiO2-Ag2O/PAA specimens was evaluated by soaking them in simulated body fluid (SBF). The surface microstructure and chemical property before and after soaking in SBF were characterized.

Highly Ordered Porous Anodic Alumina with Large Diameter Pores Fabricated by an Improved Two-Step Anodization Approach.

The aim of this study is to prepare highly ordered porous anodic alumina (PAA) with large pore sizes (> 200 nm) by an improved two-step anodization approach which combines the first hard anodization in oxalic acid-water-ethanol system and second mild anodization in phosphoric acid-water-ethanol system. The surface morphology and elemental composition of PAA are characterized by field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectrometer (EDS). The effects of matching of two-step anodizing voltages on the regularity of pore arrangement is evaluated and discussed.

Understanding improved osteoblast behavior on select nanoporous anodic alumina.

The aim of this study was to prepare different sized porous anodic alumina (PAA) and examine preosteoblast (MC3T3-E1) attachment and proliferation on such nanoporous surfaces. In this study, PAA with tunable pore sizes (25 nm, 50 nm, and 75 nm) were fabricated by a two-step anodizing procedure in oxalic acid. The surface morphology and elemental composition of PAA were characterized by field emission scanning electron microscopy and X-ray photoelectron spectroscopy analysis.

A mechanism for the enhanced attachment and proliferation of fibroblasts on anodized 316L stainless steel with nano-pit arrays.

In this study, 316L stainless steel with tunable nanometer pit sizes (0, 25, 50, and 60 nm) were fabricated by an anodization procedure in an ethylene glycol electrolyte solution containing 5 vol % perchloric acid. The surface morphology and elemental composition of the 316L stainless steel were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The nano-pit arrays on all of the 316L stainless steel samples were in a regular arrangement.

In vitro apatite formation on porous anodic alumina induced by a phosphorylation treatment.

In this study, a phosphorylation treatment of porous anodic alumina (PAA) was performed by wet impregnation in phosphoric acid and a subsequent heat treatment. The PAA and phosphorylated PAA specimens were analyzed using a field emission scanning electron microscope, an energy-dispersive X-ray spectrometer, and Fourier transform infrared spectroscopy. The apatite-forming ability of the phosphorylated PAA was evaluated by soaking the specimens in simulated body fluid for 1, 3, and 7 days.

In vitro degradation, bioactivity, and cytocompatibility of calcium silicate, dimagnesium silicate, and tricalcium phosphate bioceramics.

CaSiO3 (CS) ceramics have been regarded as a potential bioactive material for bone regeneration. Mg2SiO4 (M2S) ceramic has been reported as a novel bioceramic with higher mechanical properties and good biocompatibility recently. beta-Ca2(PO4)2 (beta-TCP) ceramic is a well-known bioactive and degradable material for bone repair.

Beta-CaSiO3/beta-Ca3(PO4)2 composite materials for hard tissue repair: in vitro studies.

In this study, a series of beta-CaSiO(3) (CS)/beta-Ca(3)(PO(4))(2) (TCP) composites with different ratios were prepared to produce new bioactive and biodegradable biomaterials for potential bone repair. The mechanical properties of CS-TCP composites increased steadily with the increase of TCP amounts in composites. Formation of bone-like apatite on a range of CS-TCP composites with CS weight percentage ranging from 0 to 100 has been investigated in simulated body fluid (SBF).

In vitro studies of novel CaO-SiO2-MgO system composite bioceramics.

In this study, a series of CaO-SiO(2)-MgO composites with different beta-CaSiO(3) (CS)/Mg(2)SiO(4) (M(2)S) composite ratios were prepared to produce new bioactive and biodegradable biomaterials for potential bone repair. The mechanical properties of CS-M(2)S composites increased steadily with the increase of M(2)S ratios in composites. Dissolution tests in Tris-HCl buffer solution showed obvious differences with different CS initial composite ratio in composites.

A novel bioactive porous bredigite (Ca7MgSi4O16) scaffold with biomimetic apatite layer for bone tissue engineering.

The aim of this study was to develop a novel bioactive, degradable and cytocompatible bredigite (Ca(7)MgSi(4)O(16)) scaffold with biomimetic apatite layer for bone tissue engineering. Porous bredigite scaffolds were prepared using polymer sponge method. The bredigite scaffolds with biomimetic apatite layer (BTAP) were obtained by soaking bredigite scaffolds in simulated body fluid (SBF) for 10 days.

Comparison of osteoblast-like cell responses to calcium silicate and tricalcium phosphate ceramics in vitro.

Calcium silicate ceramics have been proposed as new bone repair biomaterials, since they have proved to be bioactive, degradable, and biocompatible. Beta-tricalcium phosphate ceramic is a well-known degradable material for bone repair. This study compared the effects of CaSiO3 (alpha-, and beta-CaSiO3) and beta-Ca3(PO4)2 (beta-TCP) ceramics on the early stages of rat osteoblast-like cell attachment, proliferation, and differentiation.

Porous akermanite scaffolds for bone tissue engineering: preparation, characterization, and in vitro studies.

The aim of this study was to develop a bioactive, degradable, and cytocompatible akermanite (Ca2MgSi2O7) scaffold with high porosity and pore interconnectivity. In brief, porous akermanite scaffolds were prepared using polymer sponge method. The porosity and corresponding compressive strength were evaluated.

A novel bioactive porous CaSiO3 scaffold for bone tissue engineering.

The aim of this study was to fabricate bioactive porous CaSiO3 scaffolds and examine their effects on proliferation and differentiation of osteoblast-like cells. In this study, porous CaSiO3 scaffolds were obtained by sintering a ceramic slip-coated polymer foam at 1350 degrees C. X-ray diffraction (XRD) of the scaffolds indicated that the products were essentially pure alpha-CaSiO3.

In vitro bioactivity of akermanite ceramics.

In this study, the bone-like apatite-formation ability of akermanite ceramics (Ca2MgSi2O7) in simulated body fluid (SBF) and the effects of ionic products from akermanite dissolution on osteoblasts and mouse fibroblasts (cell line L929) were investigated. In addition, osteoblast morphology and proliferation on the ceramics were evaluated. The results showed that akermanite ceramics possessed bone-like apatite-formation ability comparable with bioactive wollastonite ceramics (CaSiO3) after 20 days of soaking in SBF and the mechanism of bone-like apatite formation on akermanite ceramics is similar to that of wollastonite ceramics.

Preparation and characteristics of a calcium magnesium silicate (bredigite) bioactive ceramic.

In this study, new bredigite (Ca7MgSi4O16) ceramics were prepared by sintering sol-gel-derived bredigite powder compacts at 1350 degrees C for 8 h. The bending strength, fracture toughness and Young's modulus were about 156 MPa, 1.57 MPa m(1/2) and 43 GPa, respectively.