title: Antibacterial-nanocomposite bone filler based on silver nanoparticles and polysaccharides.
abstract: Injectable bone fillers represent an attractive strategy for the treatment of bone defects. These injectable materials should be biocompatible, capable of supporting cell growth and possibly able to exert antibacterial effects. In this work, nanocomposite microbeads based on alginate, chitlac, hydroxyapatite and silver nanoparticles were prepared and characterized. The dried microbeads displayed a rapid swelling in contact with simulated body fluid and maintained their integrity for more than 30 days. The evaluation of silver leakage from the microbeads showed that the antibacterial metal is slowly released in saline solution, with less than 6% of silver released after 1 week. Antibacterial tests proved that the microbeads displayed bactericidal effects toward Staphylococcus aureus, Pseudomonas aeruginosa and Staphylococcus epidermidis, and were also able to damage pre-formed bacterial biofilms. On the other hand, the microbeads did not exert any cytotoxic effect towards osteoblast-like cells. After characterization of the microbeads bioactivity, a possible means to embed them in a fluid medium was explored in order to obtain an injectable paste. Upon suspension of the particles in alginate solution or alginate/hyaluronic acid mixtures, a homogenous and time-stable paste was obtained. Mechanical tests enabled to quantify the extrusion forces from surgical syringes, pointing out the proper injectability of the material. This novel antibacterial bone filler appears as a promising material for the treatment of bone defects, in particular when possible infections could compromise the bone-healing process. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy.|Department of Life Sciences, University of Trieste, Trieste, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Porrelli
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Travan
authors.affiliation: Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Turco
authors.affiliation: Department Chemical and Pharmaceutical Science, University of Trieste, Trieste, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Crosera
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Borgogna
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy.
authors.forename: Ivan
authors.initials: I
authors.lastname: Donati
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Paoletti
authors.affiliation: Department Chemical and Pharmaceutical Science, University of Trieste, Trieste, Italy.
authors.forename: Gianpiero
authors.initials: G
authors.lastname: Adami
authors.affiliation: Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Marsich
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects; D001842:Bone and Bones / Q000187:drug effects*; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D008863:Microspheres; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D011134:Polysaccharides / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000254:growth & development; D012834:Silver / Q000494:pharmacology*; D013212:Staphylococcus epidermidis / Q000187:drug effects / Q000254:growth & development
chemical_list: D000900:Anti-Bacterial Agents; D011134:Polysaccharides; D012834:Silver
keywords: antibacterial properties; bone healing; injectable fillers; polysaccharides; silver nanoparticles