The investigation of physical and chemical properties of collagenous tissue before and after ArF laser irradiation

Crosslinking and photodegradation mechanisms are induced by exposure to excimer laser irradiation which depends mainly on the irradiation dose. Tensile test was performed associated with the FTIR spectroscopy to investigate the changes after ArF laser irradiation on the tissue.

Samples from sheep renal capsule were irradiated by ArF excimer laser at 193nm. Young’s modulus is determined, in order to estimate the effect of irradiation in tensile test. The FTIR spectroscopy is used to study the variation of chemical and molecular structures.

Reduction of young’s modulus during 10 second exposure leads to the partial peptide bond scissions and stiffness decreasing. Aromatic acids absorption predominated between 10 to 30 sec exposure and tissue’s stiffness reaches its peak at 30 sec. Increasing the irradiation dose, the process of peptide bond scissions makes the stiffness drop and a shift of amide II frequency takes place to the lower frequency.