title: Elemental bio-imaging of calcium phosphate crystal deposits in knee samples from arthritic patients.
abstract: Laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) was employed to image deposits of calcium phosphate based crystals in knee cartilage and synovial fluid from arthritic patients. A reaction/collision cell containing hydrogen minimised plasma interferences on calcium and also improved the image quality without significant sensitivity reduction. Areas of high calcium and phosphorus intensities consistent with crystal deposits were observed for both the cartilage and synovial fluid samples. These areas were also characterised by high magnesium and strontium intensities. Distribution patterns of other elements such as copper and sulfur did not correlate with the crystal deposits. Filtered and non-filtered solutions of calcium phosphate crystals grown in synthetic synovial fluid were also imaged as further evidence of crystal deposits. The crystal deposits were detected in the unfiltered solution, and were absent from the filtered solutions.
authors.affiliation: Elemental Bio-imaging Facility, Department of Chemistry, Materials and Forensic Science, University of Technology Sydney, Sydney NSW 2007, Australia.
authors.forename: Christine
authors.initials: C
authors.lastname: Austin
authors.forename: Dominic
authors.initials: D
authors.lastname: Hare
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Rozelle
authors.forename: William H
authors.initials: WH
authors.lastname: Robinson
authors.forename: Rudolf
authors.initials: R
authors.lastname: Grimm
authors.forename: Philip
authors.initials: P
authors.lastname: Doble
mesh_terms: D002118:Calcium / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry* / Q000378:metabolism*; D002358:Cartilage, Articular / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D007554:Isotopes / Q000737:chemistry; D007719:Knee Joint / Q000737:chemistry / Q000378:metabolism; D008274:Magnesium / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D057054:Molecular Imaging / Q000379:methods*; D020370:Osteoarthritis, Knee / Q000378:metabolism*; D010758:Phosphorus / Q000737:chemistry; D013324:Strontium / Q000737:chemistry; D013582:Synovial Fluid / Q000737:chemistry / Q000378:metabolism
chemical_list: D002130:Calcium Phosphates; D007554:Isotopes; D010758:Phosphorus; D008274:Magnesium; D002118:Calcium; D013324:Strontium