PH-Responsive TiO2 Nanotube Drug Delivery System Based on Iron Coordination

Yan Liu,Xiufeng Xiao,Chunling Xie,Fengfen Zhang

doi:10.1155/2019/6395760

Yan Liu, Xiufeng Xiao + Show 2 more

Open Access

https://doi.org/10.1155/2019/6395760

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Abstract

Nanostructured materials play a fundamental role in orthopedic research owing to their outstanding properties and excellent biocompatibility. Titania nanotube (TNT) arrays engineered by electrochemical anodization process have been extensively explored and used as effective carriers for controlled drug delivery. In this study, we proposed a drug delivery system based on coordination bond. Iron (III), Fe3+, on the nanotube surface can effectively bind to alendronate sodium (NaAL), a drug for the treatment of osteoporosis, through coordination bonds, which can be formed or broken through the change of pH, and thus can be controlled by pH. The pH-responsive system was prepared by three-step procedure: (i) fabrication of TNTs by electrochemical anodization, (ii) modification of amino groups on the surface of nanotubes by hydrothermal method, and (iii) amino-functionalized nanotubes by Fe3+ solution soak. The Fe-modified TNTs not only allowed alendronate-loading content of up to 50.2% by weight, which is significantly higher than most drug delivery systems previously reported, but also delayed and prolonged drug release. Moreover, in vitro drug release experiments demonstrated that coordination bond-based TNT system may have great potential applications in clinical use.

Highlights

With the continuous developments of material and bone sciences, biomedical materials have been widely used in orthopedic field
Bone infection, a serious condition found in the orthopedics, is one of the most common clinical complications associated with bone implants
TiO2 nanotubes can be prepared by anodic oxidation of titanium substrates in dielectric solution, which are further aligned with the matrix metal

Summary

Introduction

With the continuous developments of material and bone sciences, biomedical materials have been widely used in orthopedic field. Systemic drug delivery approaches have been used traditionally to combat these clinical complications and treat bone infections or poor implant integrations. These approaches are, inefficient in reaching to the bone site, and drug overdose can cause toxicity issues and side effects in patients. Do TiO2 nanotubes have good biocompatibility, their nanotubular structures facilitate the drug loading and sustainable release. They have been used to achieve various drug delivery goals. A novel coordination bond-based pH-responsive drug delivery system, which enabled the release of drug molecules by small changes of pH, was developed [14,15,16]. The top-opened TiO2 nanotubes were aligned and organized into high-density uniform arrays with diameters ranging from 170 ± 10 nm to 200 ± 10 nm

Materials and Methods

Results and Discussion

Conclusions