title: Mesenchymal stem cell interaction with ultra-smooth nanostructured diamond for wear-resistant orthopaedic implants.
abstract: Ultra-smooth nanostructured diamond (USND) can be applied to greatly increase the wear resistance of orthopaedic implants over conventional designs. Herein we describe surface modification techniques and cytocompatibility studies performed on this new material. We report that hydrogen (H)-terminated USND surfaces supported robust mesenchymal stem cell (MSC) adhesion and survival, while oxygen- (O) and fluorine (F)-terminated surfaces resisted cell adhesion, indicating that USND can be modified to either promote or prevent cell/biomaterial interactions. Given the favorable cell response to H-terminated USND, this material was further compared with two commonly used biocompatible metals, titanium alloy (Ti-6Al-4V) and cobalt chrome (CoCrMo). MSC adhesion and proliferation were significantly improved on USND compared with CoCrMo, although cell adhesion was greatest on Ti-6Al-4V. Comparable amounts of the pro-adhesive protein, fibronectin, were deposited from serum on the three substrates. Finally, MSCs were induced to undergo osteoblastic differentiation on the three materials, and deposition of a mineralized matrix was quantified. Similar amounts of mineral were deposited onto USND and CoCrMo, whereas mineral deposition was slightly higher on Ti-6Al-4V. When coupled with recently published wear studies, these in vitro results suggest that USND has the potential to reduce debris particle release from orthopaedic implants without compromising osseointegration.
authors.affiliation: Center for Nanoscale Materials and Biointegration, Birmingham, AL 35294-1170, United States.
authors.forename: William C
authors.initials: WC
authors.lastname: Clem
authors.forename: Shafiul
authors.initials: S
authors.lastname: Chowdhury
authors.forename: Shane A
authors.initials: SA
authors.lastname: Catledge
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Weimer
authors.forename: Faheem M
authors.initials: FM
authors.lastname: Shaikh
authors.forename: Kristin M
authors.initials: KM
authors.lastname: Hennessy
authors.forename: Valery V
authors.initials: VV
authors.lastname: Konovalov
authors.forename: Michael R
authors.initials: MR
authors.lastname: Hill
authors.forename: Alfred
authors.initials: A
authors.lastname: Waterfeld
authors.forename: Susan L
authors.initials: SL
authors.lastname: Bellis
authors.forename: Yogesh K
authors.initials: YK
authors.lastname: Vohra
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry / Q000378:metabolism*; D049109:Cell Proliferation / Q000187:drug effects; D018130:Diamond / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D005353:Fibronectins / Q000378:metabolism; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry / Q000648:ultrastructure; D009985:Orthopedics / Q000379:methods; D016348:Osseointegration / Q000187:drug effects; D019736:Prostheses and Implants
chemical_list: D001672:Biocompatible Materials; D005353:Fibronectins; D018130:Diamond