Abstract
The present work characterizes the formation of free radicals in an implantable human acellular dermal tissue (Alloderm, LifeCell Corp., Branchburg, NJ) upon irradiation. The tissue was preserved in a vitreous carbohydrate matrix by freeze-drying. Freeze-dried samples were irradiated using a synchrotron light source, and free radicals generated were investigated using the electron paramagnetic resonance (EPR) technique. At least two free radical populations, with g factors of 1.993 (approximately 43%) and 2.002 (approximately 57%), respectively, were identified in the irradiated tissue. The transformation (reaction) kinetics of free radicals produced was investigated in the presence of nitrogen, oxygen and moisture. The reaction kinetics of free radicals was extremely slow in the nitrogen environment. The presence of oxygen and moisture greatly accelerated free radical reactions in the tissue matrix. The reaction of free radicals could not be described by traditional reaction kinetics. A dispersive kinetics model and a diffusion model were developed to analyze the reaction kinetics in the present study. The dispersive model took into consideration molecular mobility and dispersivity of free radicals in the heterogeneous tissue material. The diffusion model described the radical reaction kinetics as two parallel and simultaneous processes: a first-order fast kinetics mainly on tissue surface and a diffusion-limited slow kinetics in deeper layers of the tissue matrix. Both models described quantitative experimental data well. Further investigation is needed to verify whether any of these two models or concepts describes the inherent radical reaction kinetics in the solid tissue matrix.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.