Orthopedic implants from bioactive rosette nanotubes/poly(2-hydroxyethyl methacrylate)/nano-hydroxyapatite composites
- PDF / 8,134,818 Bytes
- 11 Pages / 612 x 792 pts (letter) Page_size
- 57 Downloads / 195 Views
Orthopedic implants from bioactive rosette nanotubes/poly(2-hydroxyethyl methacrylate)/nano-hydroxyapatite composites Linlin Sun,1 Lijie Zhang2, Usha D. Hemraz,3 Hicham Fenniri,3* and Thomas J. Webster1,4* 1 School of Engineering, Brown University, 182 Hope Street, Providence, RI 02912 USA 2 Department of Mechanical and Aerospace Engineering, George Washington University, 801 22nd Street, Washington, DC, USA 3 National Institute for Nanotechnology and Departments of Chemistry and Biomedical Engineering, University of Alberta, 11421 Saskatchewan Drive, Edmonton, AB T6G 2M9, Canada. 4 Department of Orthopaedics, Brown University, 593 Eddy Street, Providence, RI 02903 USA *Corresponding author: E-mail: [email protected], [email protected] ABSTRACT With multifunctionality and nanoscale dimensions, self-assembled rosette nanotubes (RNTs) exhibit unique biological and mechanical properties, making them promising to serve as a new generation of implants. Synthetic twin G^C base features the hydrogen bonding arrays of both guanine and cytosine and has the ability to self-organize spontaneously into nanotubes with a 3.5 nm outer diameter, a 1.1 nm inner channel running the length of the nanotube which can reach several micrometers in length. In this study, a twin G^C motif functionalized with an aminobutyl side chain (referred to as TBL) was synthesized, assembled into bioactive RNTs and used along with poly(2-hydroxyethyl methacrylate) (pHEMA) and hydroxyapatite (HA) nanoparticles to prepare RNTs/HA/pHEMA composites for orthopedic applications. The properties of these composites was investigated, notably the solidification process, surface morphology, mechanical properties, and cytocompatibility properties. The RNTs assembled from TBL and HA nanoparticles were found to be effective towards increasing the bioactivity of the composites thus establishing the potential of TBL/HA/pHEMA composites as very promising injectable orthopedic implant materials. INTRODUCTION Compared to traditional joint prosthetics (such as metallic, polymeric and ceramic implants), injectable materials provide a way to minimize surgical incision and tissue damage to ultimately accelerate healing [1]. The interface between bone and an injectable bone composite (such as poly(methyl methacrylate) (PMMA)) is clearly a weak-interfacial zone. To solve such a fixation problem, bioactive injectable materials that promote bone-bonding and possess mechanical properties similar to natural bone must be developed [1,2]. Therefore, many types of bioactive ceramics including hydroxyapatite (HA) and A-W Glass-Ceramics, have been added to injectables to improve cytocompatibility and mechanical properties. While improving bone growth, adding HA alone to current injectables has not provided the desired properties and new bioactive injectable chemistries are clearly needed. Supramolecular chemistry promises to create such novel injectable materials [3-7]. For example, in a previous study, one type of rosette nanotube (RNT) (Figure 1a), enhanced initial pr
Data Loading...
