Aspects of the structural integrity of chondroitin sulphate after laser irradiation

The effects of laser irradiation on molecular mass and conformation of pure chondroitin sulphate dissolved in phosphate buffered saline (PBS) were investigated using size exclusion chromatography/multi-angle light scattering (SEC/MALS) and sedimentation velocity in the analytical ultracentrifuge. In addition, cartilage pieces immersed in buffer were irradiated with a laser in order to study whether cartilage components may diffuse away from the matrix and into the surrounding aqueous medium as a result of laser treatment. Size exclusion chromatography/multi-angle light scattering and sedimentation velocity measurements showed that (a) laser irradiation decreases the molecular mass of chondroitin sulphate and (b) laser irradiation of cartilage induces diffusion of macromolecules into the medium.