Borate bioactive glasses are more soluble than silicate’s and convert rapidly and completely into hydroxyapatite (Ca5(PO4)3(OH)), being more suitable for wound healing applications than their silicate counterparts. In this work, the 45B5 composition (46.1 B2O3 – 26.9 CaO – 24.4 NaO – 2.6 P2O5, mol%)) were embedded into electrospun PHBV (Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)) nanofibers by encapsulation and/or electrospray deposition aiming to produce a wound dressing with optimized bioactivity and antibacterial properties for wound healing applications. The fibers were characterized regarding their physical, structural, and thermal properties, and in vitro by L929 Mouse Fibroblast Cell Line adhesion, migration, and cytotoxicity and by its antibacterial activity against the bacteria S. aureus. The set of characterizations evidences that the encapsulation method was the most promising for the 45B5 embedding into PHBV nanofibers, as it produced a wound dressing with great loading efficiency (70%) with a highly hydrophilic surface, leading to expressive adhesion, migration, and viability of L929 cells and antibacterial activity. Thus, the nanofibers produced by the encapsulation method alone provided a dressing with high potential in wound healing management. silicates s Ca5PO43OH, Ca5PO43OH CaPOOH Ca5 PO4 3 OH , Ca PO (Ca5(PO4)3(OH)) counterparts work B 45B 46.1 461 46 1 (46. BO O B2O 269 26 9 26. 244 24 4 24. 2 6 2. P2O5 P mol% mol mol%) Poly3hydroxybutyrateco3hydroxyvalerate Polyhydroxybutyratecohydroxyvalerate Poly hydroxybutyrate co hydroxyvalerate (Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) andor or physical structural L L92 adhesion migration S aureus 70% 70 (70% surface Thus management (Ca5(PO4)3(OH) 46. (46 P2O hydroxybutyrateco (Poly(3-hydroxybutyrate-co-3-hydroxyvalerate L9 7 (70 (Ca5(PO4)3(OH (4 (7 (

Abstract Aiming to produce an antimicrobial dressing for wound healing applications, in this work Tea Tree oil (TTO) was incorporated into PHBV nanofibers by absorption. It was observed increase in the nanofiber diameter due to 5% TTO absorption efficiency, which also led to a 54% decrease in the contact angle. The releasing assay indicates a 6.8% oil release in the first 24 h – being probably the oil deposited at the polymer surface – followed by a minimal release at 48 h. The set of antimicrobial assays performed suggests the incorporation of TTO optimized the antimicrobial activity of the polymer for E. coli and C. albicans, while against S. aureus no significant difference was observed. The MTT assay showed no cytotoxicity of PHBV, but the incubation of L929 fibroblast cells with PHBV-TTO reduced cell viability. Overall, the PHBV nanofibers containing TTO present great potential as an antimicrobial dressing. applications (TTO 5 efficiency 54 angle 68 6 8 6.8 2 4 E C albicans S L L92 PHBVTTO viability Overall 6. L9

Abstract Electrospinning is a simple and low-cost way to fabricate fibers. Among the various polymers used in electrospinning, polycaprolactone (PCL) stands out due to its excellent biodegradability and biocompatibility. However, PCL has some limitations such as low bioactivity, hydrophobic surface, and long in vivo degradation. Calcium phosphate ceramics have been recognized as an attractive biomaterial. They are bioactive and osteoinductive, and some are even quite biodegradable. Different contents of particles of beta-tricalcium phosphate (β-TCP) were incorporated in polymer matrix to form fibers of PCL/β-TCP composites by electrospinning for possible application in tissue regeneration. The presence of β-TCP particles promoted some changes in the thermal properties of the fibers. The immersion of PCL/β-TCP 8 wt-% fibers in simulated body fluid (SBF) caused the formation of a denser and homogeneous apatite layer on its surface.

Replacement tissues for tissue engineering can be produced by seeding human cells onto scaffolds. In order to guarantee adequate bio-compatibility, porosity and mechanical resistance for promoting cellular growth, proliferation and differentiation within scaffold structures, it is necessary to investigate and improve materials and processing routes. β-tricalcium phosphate can be considered a very suitable bio-ceramic material for bone therapy because of its biocompatibility, osteo-conductivity and neo-vascularization potential. Alumina is commonly used as a sintering additive. In this study, β-TCP and β-TCP/Al2O3 scaffolds were obtained by gel-casting method. The scaffolds showed high porosity (86-88%) and pore sizes ranging from 200 to 500 µm. Even though alumina did not promote improvement in β-TCP/Al2O3 scaffolds in terms of mechanical performance, they showed great cytocompatibility as there was no cytotoxic and genotoxic effect. Therefore, β-TCP and β-TCP/Al2O3 scaffolds are good candidates for application in tissue engineering.

The austenitic stainless steel 316L is the most used metallic biomaterials in orthopedics applications, especially in the manufacture of articulated prostheses and as structural elements in fracture fixation, since it has high mechanical strength. However, because it is biologically inactive, it does not form chemical bond with bone tissue, it is fixed only by morphology. The development of biocomposites of stainless steel with a bioactive material, such as hydroxyapatite - HA, is presented as an alternative to improve the response in the tissue-implant interface. However significant reductions in mechanical properties of the biocomposite can occur. Different compositions of the biocomposite stainless steel 316L/HA (5, 20 and 50 wt. (%) HA) were prepared by mechanical alloying. After milling the powders for 10 hours, the different compositions of the biocomposite were compacted isostatically and sintered at 1200 ºC for 2 hours. The mechanical properties of the biocomposites were analyzed by compression tests. The powders and the sintered composites were analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD).