Methods for the analysis of the composition of bone tissue, with a focus on imaging mass spectrometry (TOF-SIMS).

The review describes methods available for analyzing mineralization of bone tissue in healing of fractures and implants in bone. The recent development of imaging MS, TOF-secondary ion MS (SIMS), enabling localization of hydroxyapatite (HA) in tissue samples will be presented in some detail. We strongly believe that imaging MS has the potential of becoming an important method for the studies of bone mineralization. Formation and mineralization of bone tissue with HA is a process controlled by cells, the osteoblasts, osteocytes, and osteoclasts. Formation, de novo, of bone in embryonic tissue takes place in extracellular areas within cell clusters that regulate the environment of the mineralization zone. The process of de novo formation of bone as in embryonic tissue is reactivated in adults for example during fracture healing, with or without the presence of bone implants. Thus, bone healing is one of few examples of scar-free healing of a differentiated tissue. Much of the interest of researchers in bone mineralization stems from a desire to influence the process of bone formation towards fast and endurable bone healing. There is also a wish to understand the pathogenesis of bone diseases, for example osteogenesis imperfecta, Turner's syndrome and osteoporosis.