Birefringence and Second Harmonic Generation on Tendon Collagen Following Red Linearly Polarized Laser Irradiation |
| |
Authors: | Daniela Fátima Teixeira Silva Anderson Stevens Leonidas Gomes Benedicto de Campos Vidal Martha Simões Ribeiro |
| |
Institution: | 1. Post-Graduation Program in Biophotonics Applied to Health Sciences, Universidade Nove de Julho (UNINOVE), S?o Paulo, SP, 01504-001, Brazil 4. Centro de Lasers e Aplica??es, IPEN-CNEN/SP, S?o Paulo, SP, 05508-900, Brazil 2. Departamento de Física, CCEN-UFPE, Recife, PE, 50670-901, Brazil 3. Instituto de Biologia, IB-UNICAMP, Campinas, SP, 13084-971, Brazil
|
| |
Abstract: | Regarding the importance of type I collagen in understanding the mechanical properties of a range of tissues, there is still a gap in our knowledge of how proteins perform such work. There is consensus in literature that the mechanical characteristics of a tissue are primarily determined by the organization of its molecules. The purpose of this study was to characterize the organization of non-irradiated and irradiated type I collagen. Irradiation was performed with a linearly polarized HeNe laser (λ = 632.8 nm) and characterization was undertaken using polarized light microscopy to investigate the birefringence and second harmonic generation to analyze nonlinear susceptibility. Rats received laser irradiation (P = 6.0 mW, I = 21.2 mW/cm2, E ≈ 0.3 J, ED = 1.0 J/cm2) on their healthy Achilles tendons, which after were extracted to prepare the specimens. Our results show that irradiated samples present higher birefringence and greater non-linear susceptibility than non-irradiated samples. Under studied conditions, we propose that a red laser with polarization direction aligned in parallel to the tendon long axis promotes further alignment on the ordered healthy collagen fibrils towards the electric field incident. Thus, prospects for biomedical applications for laser polarized radiation on type I collagen are encouraging since it supports greater tissue organization. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|