In situ fabrication of silver nanoparticle-filled hydrogen titanate nanotube layer on metallic titanium surface for bacteriostatic and biocompatible implantation

Abstract

Zheng Wang,1 Yan Sun,1 Dongzhou Wang,2 Hong Liu,2 Robert I Boughton31Department of Cardiology, Heilongjiang Provincial Hospital, Haerbin, Heilongjiang, People’s Republic of China; 2State Key Laboratory of Crystal Materials, Shandong University, Jinan, People’s Republic of China; 3Department of Physics and Astronomy, Bowling Green State University, Bowling Green, OH, USAAbstract: A silver nanoparticle (AgNP)-filled hydrogen titanate nanotube layer was synthesized in situ on a metallic titanium substrate. In the synthesis approach, a layer of sodium titanate nanotubes is first prepared on the titanium surface by using a hydrothermal method. Silver nitrate solution is absorbed into the nanotube channels by immersing a dried nanotube layer in silver nitrate solution. Finally, silver ions are reduced by glucose, leading to the in situ growth of AgNPs in the hydrogen titanate nanotube channels. Long-term silver release and bactericidal experiments demonstrated that the effective silver release and effective antibacterial period of the titanium foil with a AgNP-filled hydrogen titanate nanotube layer on the surface can extend to more than 15 days. This steady and prolonged release characteristic is helpful to promote a long-lasting antibacterial capability for the prevention of severe infection after surgery. A series of antimicrobial and biocompatible tests have shown that the sandwich nanostructure with a low level of silver loading exhibits a bacteriostatic rate as high as 99.99%, while retaining low toxicity for cells and possessing high osteogenic potential. Titanium foil with a AgNP-filled hydrogen titanate nanotube layer on the surface that is fabricated with low-cost surface modification methods is a promising implantable material that will find applications in artificial bones, joints, and dental implants.Keywords: titanium implant, silver nanoparticle filling, ion substitution, bacteriostasis, cytocompatibility