Improving our understanding of metal implant failures: Multiscale chemical imaging of exogenous metals in ex-vivo biological tissues

DOI: 10.1016/j.actbio.2019.05.071

Authors: Alexander P. Morrell (University of Aston) , Hayley Floyd (University of Birmingham) , J. Frederick W. Mosselmans (Diamond Light Source) , Liam M. Grover (University of Birmingham) , Hiram Castillo-Michel (European Synchrotron Radiation Facility) , Edward Davis (University Hospitals Birmingham) , Julia E. Parker (Diamond Light Source) , Richard Martin (University of Aston) , Owen Addison (University of Birmingham; University of Alberta)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Acta Biomaterialia

State: Published (Approved)
Published: June 2019

Abstract: Biological exposures to micro- and nano-scale exogenous metal particles generated as a consequence of in-service degradation of orthopaedic prosthetics can result in severe adverse tissues reactions. However, individual reactions are highly variable and are not easily predicted, due to in part a lack of understanding of the speciation of the metal-stimuli which dictates cellular interactions and toxicity. Investigating the chemistry of implant derived metallic particles in biological tissue samples is complicated by small feature sizes, low concentrations and often a heterogeneous speciation and distribution. These challenges were addressed by developing a multi-scale two-dimensional X-ray absorption spectroscopic (XAS) mapping approach to discriminate sub-micron changes in particulate chemistry within ex-vivo tissues associated with failed CoCrMo total hip replacements (THRs). As a result, in the context of THRs, we demonstrate much greater variation in Cr chemistry within tissues compared with previous reports. Cr compounds including phosphate, hydroxide, oxide, metal and organic complexes were observed and correlated with Co and Mo distributions. This variability may help explain the lack of agreement between biological responses observed in experimental exposure models and clinical outcomes. The multi-scale 2D XAS mapping approach presents an essential tool in discriminating the chemistry in dilute biological systems where speciation heterogeneity is expected.

Journal Keywords: XANES mapping; metal particle chemistry; microfocus spectroscopy; XRF; CoCr chemistry; total hip replacement

Subject Areas: Biology and Bio-materials, Chemistry, Medicine


Instruments: I14-Hard X-ray Nanoprobe , I18-Microfocus Spectroscopy

Other Facilities: ESRF; Swiss Light Source

Added On: 10/06/2019 14:06

Documents:
mjj5.pdf

Discipline Tags:

Biotech & Biological Systems Biomaterials Molecular Complexes Chemistry Materials Science Organic Chemistry Life Sciences & Biotech Metallurgy

Technical Tags:

Imaging Spectroscopy X-ray Fluorescence (XRF) X-ray Absorption Spectroscopy (XAS) X-ray Absorption Near Edge Structure (XANES)