title: Birefringence measurement of rapid structural changes during collagen denaturation.
abstract: Linear birefringence, an optical property that results from a material's structure and composition, can be used to study dynamic changes in tissue structure. Single, 200 microseconds-long pulses from a Ho:YAG laser emitting 2.1 microns radiation were used to induce changes in the linear birefringence of rat tail tendon. Such changes were measured on a millisecond timescale. The measured rate coefficients describing the denaturation are not predicted by previous studies of collagen denaturation induced by slower, lower-temperature heating. Two types of laser-induced collagen denaturation can be differentiated: thermal denaturation, which appears rate-limited, and thermomechanical denaturation, which is observed at higher laser radiant exposures. Neither process is described by standard Arrhenius-type kinetic models.
authors.affiliation: Biomedical Engineering Department, Northwestern University, Evanston, IL 60208, USA.
authors.forename: V
authors.initials: V
authors.lastname: Sankaran
authors.forename: J T
authors.initials: JT
authors.lastname: Walsh
mesh_terms: D000818:Animals; D001718:Birefringence; D003094:Collagen / Q000737:chemistry*; D007700:Kinetics; D007834:Lasers; D011489:Protein Denaturation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013696:Temperature
chemical_list: D003094:Collagen