title: Titanium Surface Priming with Phase-Transited Lysozyme to Establish a Silver Nanoparticle-Loaded Chitosan/Hyaluronic Acid Antibacterial Multilayer via Layer-by-Layer Self-Assembly.
abstract: OBJECTIVE
  The formation of biofilm around implants, which is induced by immediate bacterial colonization after installation, is the primary cause of post-operation infection. Initial surface modification is usually required to incorporate antibacterial agents on titanium (Ti) surfaces to inhibit biofilm formation. However, simple and effective priming methods are still lacking for the development of an initial functional layer as a base for subsequent coatings on titanium surfaces. The purpose of our work was to establish a novel initial layer on Ti surfaces using phase-transited lysozyme (PTL), on which multilayer coatings can incorporate silver nanoparticles (AgNP) using chitosan (CS) and hyaluronic acid (HA) via a layer-by-layer (LbL) self-assembly technique.
  
  
  METHODS
  In this study, the surfaces of Ti substrates were primed by dipping into a mixture of lysozyme and tris(2-carboxyethyl)phosphine (TCEP) to obtain PTL-functionalized Ti substrates. The subsequent alternating coatings of HA and chitosan loaded with AgNP onto the precursor layer of PTL were carried out via LbL self-assembly to construct multilayer coatings on Ti substrates.
  
  
  RESULTS
  The results of SEM and XPS indicated that the necklace-like PTL and self-assembled multilayer were successfully immobilized on the Ti substrates. The multilayer coatings loaded with AgNP can kill planktonic and adherent bacteria to 100% during the first 4 days. The antibacterial efficacy of the samples against planktonic and adherent bacteria achieved 65%-90% after 14 days. The sustained release of Ag over 14 days can prevent bacterial invasion until mucosa healing. Although the AgNP-containing structure showed some cytotoxicity, the toxicity can be reduced by controlling the Ag release rate and concentration.
  
  
  CONCLUSIONS
  The PTL priming method provides a promising strategy for fabricating long-term antibacterial multilayer coatings on titanium surfaces via the LbL self-assembly technique, which is effective in preventing implant-associated infections in the early stage.
authors.affiliation: School of Dentistry, Hospital of Stomatology, Tianjin Medical University, Tianjin, PR China.
authors.forename: Xue
authors.initials: X
authors.lastname: Zhong
authors.affiliation: School of Dentistry, Hospital of Stomatology, Tianjin Medical University, Tianjin, PR China.
authors.forename: Yunjia
authors.initials: Y
authors.lastname: Song
authors.affiliation: Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Yang
authors.affiliation: School of Dentistry, Hospital of Stomatology, Tianjin Medical University, Tianjin, PR China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Dentistry, Hospital of Stomatology, Tianjin Medical University, Tianjin, PR China.
authors.forename: Shaoyun
authors.initials: S
authors.lastname: Jiang
authors.affiliation: School of Dentistry, Hospital of Stomatology, Tianjin Medical University, Tianjin, PR China.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.affiliation: School of Dentistry, Hospital of Stomatology, Tianjin Medical University, Tianjin, PR China.
authors.forename: Changyi
authors.initials: C
authors.lastname: Li
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000494:pharmacology; D015921:Dental Implants / Q000382:microbiology; D006820:Hyaluronic Acid / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D051379:Mice; D012834:Silver / Q000737:chemistry*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D020099:Coated Materials, Biocompatible; D015921:Dental Implants; D012834:Silver; D006820:Hyaluronic Acid; D048271:Chitosan; D014025:Titanium