An FT-IR Spectral Analysis of the Effects of γ-Radiation on Normal and Cancerous Cartilage.

In the present study we used non-distractive physicochemical methods to investigate the effect of γ-radiation on human articular cartilage. Comparison between the FT-IR (Fourier transform infrared) spectra before and after irradiation of the cartilage with different doses of radiation showed considerable changes in the spectra. It was found that for doses up to 2 Gy the collagen helices changed their structure from α-helix to random coil. By increasing the radiation dose it was found that the proteins' structure changed further to amyloid-like protein formation and to fragments of glycosaminoglycan chains, which were indicated in the IR spectra. Furthermore, comparison between the spectra of normal and irradiated cartilage, cancerous cartilage and cartilage from patients who received radiotherapy showed similarities in the spectra together with the formation of an aldehyde absorption band at 1740 cm(-1) suggesting that in all cases of cartilage examined,oxidative stress played major role in the damage progression of cartilage.