Research on osteoporosis based on Raman spectroscopy and imaging

Bone is a complex connective tissue composed primarily of organic collagen and inorganic minerals such as hydroxyapatite. Hydroxyapatite gives bone strength, while collagen provides toughness, and together they maintain the biomechanical properties of bone. However, when bone mass decreases and the bone microstructure is damaged, osteoporosis is triggered, increasing the risk of fracture. Raman spectroscopy and Raman imaging were used to characterize bone without labeling. First, Raman spectra of cancellous bone in the femur of normal and ovariectomized rats were measured. The results showed that the mineral-to-matrix ratio, crystallinity and collagen cross-linking were reduced in the bone tissue of ovariectomized rats compared to normal rats. In contrast, the degree of carbonate replacement was increased, thus highlighting compositional differences between normal and ovariectomized osteoporosis-affected bone. In addition, the relevant regions of the rat femur were visually analyzed using Raman imaging. This clearly showed the distribution of various components in the bone tissue. Raman spectra and imaging results can be used to determine the proportions and spatial distribution of individual components in bone tissue. This provides a new perspective for an in-depth study of osteoporosis.