title: Does implant coating with antibacterial-loaded hydrogel reduce bacterial colonization and biofilm formation in vitro?
abstract: BACKGROUND
  Implant-related infections represent one of the most severe complications in orthopaedics. A fast-resorbable, antibacterial-loaded hydrogel may reduce or prevent bacterial colonization and biofilm formation of implanted biomaterials.
  
  
  OBJECTIVE
  We asked: (1) Is a fast-resorbable hydrogel able to deliver antibacterial compounds in vitro? (2) Can a hydrogel (alone or antibacterial-loaded) coating on implants reduce bacterial colonization? And (3) is intraoperative coating feasible and resistant to press-fit implant insertion?
  
  
  METHODS
  We tested the ability of Disposable Antibacterial Coating (DAC) hydrogel (Novagenit Srl, Mezzolombardo, Italy) to deliver antibacterial agents using spectrophotometry and a microbiologic assay. Antibacterial and antibiofilm activity were determined by broth microdilution and a crystal violet assay, respectively. Coating resistance to press-fit insertion was tested in rabbit tibias and human femurs.
  
  
  RESULTS
  Complete release of all tested antibacterial compounds was observed in less than 96 hours. Bactericidal and antibiofilm effect of DAC hydrogel in combination with various antibacterials was shown in vitro. Approximately 80% of the hydrogel coating was retrieved on the implant after press-fit insertion.
  
  
  CONCLUSIONS
  Implant coating with an antibacterial-loaded hydrogel reduces bacterial colonization and biofilm formation in vitro.
  
  
  CONCLUSIONS
  A fast-resorbable, antibacterial-loaded hydrogel coating may help prevent implant-related infections in orthopaedics. However, further validation in animal models and properly controlled human studies is required.
authors.affiliation: Dipartimento di Chirurgia Ricostruttiva e delle Infezioni Osteo-articolari, Istituto Ortopedico IRCCS Galeazzi, Via Riccardo Galeazzi, 4, Milano, 20161, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Drago
authors.forename: Willemijn
authors.initials: W
authors.lastname: Boot
authors.forename: Kostantinos
authors.initials: K
authors.lastname: Dimas
authors.forename: Kostantinos
authors.initials: K
authors.lastname: Malizos
authors.forename: Gertrud M
authors.initials: GM
authors.lastname: Hänsch
authors.forename: Jos
authors.initials: J
authors.lastname: Stuyck
authors.forename: Debby
authors.initials: D
authors.lastname: Gawlitta
authors.forename: Carlo L
authors.initials: CL
authors.lastname: Romanò
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D018441:Biofilms / Q000187:drug effects*; D020099:Coated Materials, Biocompatible / Q000494:pharmacology*; D004337:Drug Carriers; D016503:Drug Delivery Systems / Q000379:methods*; D005240:Feasibility Studies; D005269:Femur / Q000382:microbiology / Q000601:surgery; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D066298:In Vitro Techniques; D008826:Microbial Sensitivity Tests; D016459:Prosthesis-Related Infections / Q000382:microbiology* / Q000517:prevention & control*; D011817:Rabbits; D013211:Staphylococcus aureus / Q000187:drug effects; D013212:Staphylococcus epidermidis / Q000187:drug effects; D013977:Tibia / Q000382:microbiology / Q000601:surgery
chemical_list: D000900:Anti-Bacterial Agents; D020099:Coated Materials, Biocompatible; D004337:Drug Carriers; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate