TY - JOUR
T1 - Enhancement in Sustained Release of Antimicrobial Peptide from Dual-Diameter-Structured TiO2 Nanotubes for Long-Lasting Antibacterial Activity and Cytocompatibility
AU - Zhang, Yanni
AU - Zhang, Lan
AU - Li, Bo
AU - Han, Yong
N1 - Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/3/22
Y1 - 2017/3/22
N2 - Novel films on Ti-based orthopedic implants for localized antimicrobial delivery, which comprises dual-diameter TiO2 nanotubes with the inner layers of compact and fluorine-free oxide tightly bonding to Ti, were formed by voltage-increased anodization with F- sedimentation procedure. The nanotubes were closely aligned and structured with upper 35 and 70 nm diametric tubes as nanocaps, respectively, and the underlying 140 nm diametric tubes as nanoreservoirs. Followed by loading ponericin G1 (a kind of antimicrobial peptide (AMP)) into the dual-diameter nanotubes with vacuum-assisted physisorption, the resultant films were investigated for loading efficiency and release kinetics of AMP, antibacterial activity against Staphylococcus aureus, and osteoblastic compatibility, together with the AMP-loaded single-diameter (140 nm) nanotube film. The loaded films had no statistical difference in the loading efficiency of AMP and revealed burst release within 6 h followed by steady release of AMP in phosphate-buffered solution. At day 42, almost all of AMP was released from the single-diameter nanotube film. However, the dual-diameter nanotube films loaded with AMP still showed sustained release at least up to 60 days, and the sustained efficacy was enhanced with decreasing diameter of nanocaps. In the case of nominal AMP loading amount of 125 μg, the resultant 35 nm capped dual-diameter nanotube film exhibited significant short- and long-term (even for 49 days) antibacterial activity not only against planktonic bacteria, which is ascribed to the release-killing efficacy of AMP, but also against adhered bacteria, which is ascribed to the AMP-derived killing efficacy and the nanocaps-derived adhesion resistance. Moreover, this loaded film presented cytocompatibility comparative to that of Ti but higher than that of the other AMP-loaded films. Increasing the nominal loading amount of AMP to 200 μg improved antibacterial activity but gave rise to obvious cytotoxicity of the loaded films.
AB - Novel films on Ti-based orthopedic implants for localized antimicrobial delivery, which comprises dual-diameter TiO2 nanotubes with the inner layers of compact and fluorine-free oxide tightly bonding to Ti, were formed by voltage-increased anodization with F- sedimentation procedure. The nanotubes were closely aligned and structured with upper 35 and 70 nm diametric tubes as nanocaps, respectively, and the underlying 140 nm diametric tubes as nanoreservoirs. Followed by loading ponericin G1 (a kind of antimicrobial peptide (AMP)) into the dual-diameter nanotubes with vacuum-assisted physisorption, the resultant films were investigated for loading efficiency and release kinetics of AMP, antibacterial activity against Staphylococcus aureus, and osteoblastic compatibility, together with the AMP-loaded single-diameter (140 nm) nanotube film. The loaded films had no statistical difference in the loading efficiency of AMP and revealed burst release within 6 h followed by steady release of AMP in phosphate-buffered solution. At day 42, almost all of AMP was released from the single-diameter nanotube film. However, the dual-diameter nanotube films loaded with AMP still showed sustained release at least up to 60 days, and the sustained efficacy was enhanced with decreasing diameter of nanocaps. In the case of nominal AMP loading amount of 125 μg, the resultant 35 nm capped dual-diameter nanotube film exhibited significant short- and long-term (even for 49 days) antibacterial activity not only against planktonic bacteria, which is ascribed to the release-killing efficacy of AMP, but also against adhered bacteria, which is ascribed to the AMP-derived killing efficacy and the nanocaps-derived adhesion resistance. Moreover, this loaded film presented cytocompatibility comparative to that of Ti but higher than that of the other AMP-loaded films. Increasing the nominal loading amount of AMP to 200 μg improved antibacterial activity but gave rise to obvious cytotoxicity of the loaded films.
KW - antibacterial activity
KW - antimicrobial peptide
KW - controllable release
KW - cytocompatibility
KW - dual-diameter nanotube film
UR - https://www.scopus.com/pages/publications/85015958228
U2 - 10.1021/acsami.7b00322
DO - 10.1021/acsami.7b00322
M3 - 文章
C2 - 28240853
AN - SCOPUS:85015958228
SN - 1944-8244
VL - 9
SP - 9449
EP - 9461
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 11
ER -