Chitosan/hydroxyapatite composite bone tissue engineering scaffolds with dual and decoupled therapeutic ion delivery: copper and strontium.

Therapeutic metal ions are a family of metal ions characterized by specific biological properties that could be exploited in bone tissue engineering, avoiding the use of expensive and potentially problematic growth factors and other sensitive biomolecules. In this work, we report the successful preparation and characterization of two material platforms containing therapeutic ions: a copper(ii)-chitosan derivative and a strontium-substituted hydroxyapatite. These biomaterials showed ideal ion release profiles, offering burst release of an antibacterial agent together with a more sustained release of strontium in order to achieve long-term osteogenesis.

Collagen scaffolds functionalised with copper-eluting bioactive glass reduce infection and enhance osteogenesis and angiogenesis both in vitro and in vivo.

The bone infection osteomyelitis (typically by Staphylococcus aureus) usually requires a multistep procedure of surgical debridement, long-term systemic high-dose antibiotics, and - for larger defects - bone grafting. This, combined with the alarming rise in antibiotic resistance, necessitates development of alternative approaches. Herein, we describe a one-step treatment for osteomyelitis that combines local, controlled release of non-antibiotic antibacterials with a regenerative collagen-based scaffold.

Development and Characterization of Bioactive Glass Containing Composite Coatings with Ion Releasing Function for Antibiotic-Free Antibacterial Surgical Sutures.

Resorbable (Vicryl Plus) sutures were coated with zinc-doped glass (Zn-BG) and silver-doped ordered mesoporous bioactive glass (Ag-MBG) particles by a dip coating technique. A multilayer approach was used to achieve robust coatings. The first coating was a polymeric layer (e.

Gelatin coating increases in vivo bone formation capacity of three-dimensional 45S5 bioactive glass-based crystalline scaffolds.

Recent studies have demonstrated that surface characteristics, porosity, and mechanical strength of three-dimensional 45S5-type bioactive glass (BG)-based scaffolds are directly correlated with osteogenic properties. Three-dimensional BG-based scaffolds obtained from maritime natural sponges (MNSs) as sacrificial templates exhibit the required morphological properties; however, no in vivo data about the osteogenic features are available. In this study, uncoated (Group A) and gelatin-coated (Group B) crystalline MNS-obtained BG-based scaffolds were evaluated mechanically and seeded with human mesenchymal stem cells prior to subcutaneous implantation in immunodeficient mice.

Tackling bioactive glass excessive in vitro bioreactivity: Preconditioning approaches for cell culture tests.

Unlabelled: Bioactive glasses (BGs) are being increasingly considered for biomedical applications in bone and soft tissue replacement approaches thanks to their ability to form strong bonding with tissues. However, due to their high reactivity once in contact with water-based solutions BGs rapidly exchange ions with the surrounding environment leading in most cases to an undesired increase of the pH under static in vitro conditions (due to alkaline ion "burst release"), making difficult or even impossible to perform cell culture studies. Several pre-conditioning treatments have been therefore proposed in laboratories worldwide to limit this problem.

Synthesis and Characterization of Silver-Doped Mesoporous Bioactive Glass and Its Applications in Conjunction with Electrospinning.

Since they were first developed in 2004, mesoporous bioactive glasses (MBGs) rapidly captured the interest of the scientific community thanks to their numerous beneficial properties. MBGs are synthesised by a combination of the sol⁻gel method with the chemistry of surfactants to obtain highly mesoporous (pore size from 5 to 20 nm) materials that, owing to their high surface area and ordered structure, are optimal candidates for controlled drug-delivery systems. In this work, we synthesised and characterised a silver-containing mesoporous bioactive glass (Ag-MBG).

Electrophoretic Deposition of Chitosan/45S5 Bioactive Glass Composite Coatings Doped with Zn and Sr.

In this research work, the original 45S5 bioactive glass was modified by introducing zinc and/or strontium oxide (6 mol%) in place of calcium oxide. Sr was added for its ability to stimulate bone formation and Zn for its role in bone metabolism, antibacterial properties, and anti-inflammatory effect. The glasses were produced by means of melting and quenching process.