Advanced biopolymer-coated drug-releasing titania nanotubes (TNTs) implants with simultaneously enhanced osteoblast adhesion and antibacterial properties

• Published in: Colloids and surfaces, B, Biointerfaces B, Biointerfaces, 2015-06, Vol.130, p.255-263
• Main Authors: Kumeria, Tushar, Mon, Htwe, Aw, Moom Sinn, Gulati, Karan, Santos, Abel, Griesser, Hans J., Losic, Dusan
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacokinetics; Anti-Bacterial Agents - pharmacology; Biofilms - drug effects; Biofilms - growth & development; Biopolymer coating; Biopolymers - chemistry; Bone implants; Cell Adhesion - drug effects; Cell Line, Tumor; Coated Materials, Biocompatible - chemistry; Delayed-Action Preparations - chemistry; Delayed-Action Preparations - pharmacokinetics; Delayed-Action Preparations - pharmacology; Drug Implants; Drug release; Gentamicins - chemistry; Gentamicins - pharmacokinetics; Gentamicins - pharmacology; Humans; Micelles; Microbial Viability - drug effects; Microscopy, Electron, Scanning; Nanotubes - chemistry; Nanotubes - ultrastructure; Osteoblast cells; Osteoblasts - cytology; Staphylococcus epidermidis; Staphylococcus epidermidis - drug effects; Staphylococcus epidermidis - physiology; Titania nanotubes; Titanium - chemistry
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2015.04.021

•We fabricate TiO2 nanotubes (TNTs) with controlled pore diameter and length on Ti substrate.•Drug loading and release capabilities of these TNTs were explored using gentamicin as model drug. Drug release kinetics and burst release from TNTs were further controlled by biopolymer coating.•Osteoblast adhesion activity suggested improved cell adhesion on TNT surfaces than control surfaces (Ti plate or plastic surface). Osteoblast adhesion was greatest for biopolymer-coated TNT substrates (especially chitosan).•Antibacterial properties of gentamicin-loaded TNTs suggest improved and long-term antibacterial effect from biopolymer-coated TNTs substrates.•Chitosan-coated TNTs displayed the best antibacterial and anti-biofilm formation capabilities.•Altogether, biopolymer-coated TNTs displayed simultaneous osteoblast adhesion and antibacterial properties. Here, we report on the development of advanced biopolymer-coated drug-releasing implants based on titanium (Ti) featuring titania nanotubes (TNTs) on its surface. These TNT arrays were fabricated on the Ti surface by electrochemical anodization, followed by the loading and release of a model antibiotic drug, gentamicin. The osteoblastic adhesion and antibacterial properties of these TNT–Ti samples are significantly improved by loading antibacterial payloads inside the nanotubes and modifying their surface with two biopolymer coatings (PLGA and chitosan). The improved osteoblast adhesion and antibacterial properties of these drug-releasing TNT–Ti samples are confirmed by the adhesion and proliferation studies of osteoblasts and model Gram-positive bacteria (Staphylococcus epidermidis). The adhesion of these cells on TNT–Ti samples is monitored by fluorescence and scanning electron microscopies. Results reveal the ability of these biopolymer-coated drug-releasing TNT–Ti substrates to promote osteoblast adhesion and proliferation, while effectively preventing bacterial colonization by impeding their proliferation and biofilm formation. The proposed approach could overcome inherent problems associated with bacterial infections on Ti-based implants, simultaneously enabling the development of orthopedic implants with enhanced and synergistic antibacterial functionalities and bone cell promotion.