title: Local delivery of antimicrobial peptides using self-organized TiO2 nanotube arrays for peri-implant infections.
abstract: Peri-implant infections have been reported as one of the major complications that lead to the failure of orthopedic implants. An ideal solution to the peri-implant infection is to locally deliver antimicrobial agents through the implant surface. The rising problem of infections caused by multiple antibiotic-resistant bacteria makes traditional antibiotics less desirable for the prevention of peri-implant infections. One of the promising alternatives is the family of antimicrobial peptides (AMPs). In this study, we report the local delivery of AMPs through the nanotubular structure processed on titanium surface. Self-organized and vertically oriented TiO2 nanotubes, about 80 nm in diameter and 7 μm thick, were prepared by the anodization technique. HHC-36 (KRWWKWWRR), one of the most potent broad-spectrum AMPs, was loaded onto the TiO2 nanotubes via a simple vacuum-assisted physical adsorption method. Antimicrobial activity testing against Gram-positive bacterium, Staphylococcus aureus, demonstrated that this AMP-loaded nanotubular surface could effectively kill the bacteria (≈ 99.9% killing) and reduce the total bacterial number adhered to the surface after 4 h of culture. In vitro AMP elution from the nanotubes was investigated using liquid chromatography-mass spectrometry (LC-MS). The release profiles strongly depended on the crystallinity of the TiO2 nanotubes. Anatase TiO2 nanotubes released significantly higher amounts of AMP than amorphous nanotubes during the initial burst release stage. Both followed almost the same slow release profile from 4 h up to 7 days. Despite the differences in release kinetics, no significant difference was observed between these two groups in bactericidal efficiency.
authors: Department of Materials Engineering, University of British Columbia, Vancouver, BC, Canada.
authors: Menghan
authors: M
authors: Ma
authors: Mehdi
authors: M
authors: Kazemzadeh-Narbat
authors: Yu
authors: Y
authors: Hui
authors: Shanshan
authors: S
authors: Lu
authors: Chuanfan
authors: C
authors: Ding
authors: David D Y
authors: DD
authors: Chen
authors: Robert E W
authors: RE
authors: Hancock
authors: Rizhi
authors: R
authors: Wang
mesh_terms: D000595:Amino Acid Sequence; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000627:therapeutic use*; D001422:Bacterial Adhesion / Q000187:drug effects; D015169:Colony Count, Microbial; D016503:Drug Delivery Systems; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D016459:Prosthesis-Related Infections / Q000188:drug therapy*; D013059:Spectrum Analysis, Raman; D013211:Staphylococcus aureus / Q000187:drug effects / Q000254:growth & development; D014025:Titanium / Q000737:chemistry*
chemical_list: D023181:Antimicrobial Cationic Peptides; C009495:titanium dioxide; D014025:Titanium