AVS 50th International Symposium
    Biomaterial Interfaces Tuesday Sessions
       Session BI-TuP

Paper BI-TuP22
A Comparative Study of Bone Cell Attachment and Spreading on Various Metal Surfaces by Cryo-SEM and QCM-D

Tuesday, November 4, 2003, 5:30 pm, Room Hall A-C

Session: Poster Session
Presenter: M. Foss, University of Aarhus, Denmark
Authors: M. Foss, University of Aarhus, Denmark
J. Justesen, University of Aarhus, Denmark
M. Duch, University of Aarhus, Denmark
A.-L. Stranne, University of Aarhus, Denmark
J. Chevallier, University of Aarhus, Denmark
C. Modin, University of Aarhus, Denmark
F.S. Pedersen, University of Aarhus, Denmark
F. Besenbacher, University of Aarhus, Denmark
Correspondent: Click to Email
The detailed understanding of the attachment of bone-forming cells on surfaces is crucial for the development of new generations of orthopaedic implant materials. The goal of these studies is to establish methods for a more quantitative measurement of biocompatibility. Here, traditional methods of cell counting and cell area measurements are correlated with data obtained by the Quartz Crystal Microbalance technique (QCM-D, Q-Sense AB) of cell attachment and spreading. The spreading and attachment of the murine preosteoblastic MC3T3-E1 cells were quantified by cryo-SEM. Cells were seeded and allowed to attach for various periods of time, fixed and snap-frozen in liquid nitrogen. The number of attached cells and the mean area were determined using a standard image analysis program. After attachment the shape of the cells changes from round to an initial maximum spread at the surface. The time-scale for maximum spread at serum-free conditions has been determined to 40 - 50 min, which is in good agreement with QCM-D data where the maximum shifts in both frequency and dissipation are reached at similar time points. The examinations have been applied to several relevant metal surfaces including tantalum and chromium. At cell concentrations ranging from 50,000 cells/ml to 300,000 cells/ml, a variation in the degree of cell spreading is observed between these two metals implying differences in the cell attachment at the chemically different surfaces. However, the viscoelastic properties of the cells are independent of the substrate material. The results point to the establishment of a fast and accurate general method for screening biomaterials with QCM-D. The methods will furthermore be applied to surfaces functionalized by prototype proteins including BSA and fibronectin.