Evaluation of Biomechanical and Chemical Properties of Gamma-Irradiated Polycaprolactone Microfilaments for Musculoskeletal Tissue Engineering Applications

Abstract

An appropriate and reliable sterilization technique is crucial for tissue engineering scaffolds. Skeletal muscle scaffolds are often fabricated using microfilaments of a wide variety of polymers. One method for sterilization is 25 kGy of gamma irradiation. In addition, sterilization through irradiation should administer a dose within a specific range. Radiation directly affects the chemical and mechanical properties of scaffolds. The accuracy and effects of irradiation are often not considered during sterilization procedures; however, these are important since they provide insight on whether the sterilization procedure is reliable and reproducible. This study focused on the chemical and mechanical characterization of 25 kGy gamma-irradiated scaffold. The accuracy and uncertainty of the irradiation procedure were also obtained. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analyses were performed to determine whether the crystallinity of the polymer changed after irradiation and whether gamma rays influenced its thermal properties. The tensile parameters of the microfilaments were analyzed by comparing irradiated and nonirradiated scaffolds to determine whether gamma radiation changed their elastic behavior. Dose distribution and uncertainty were recorded with several dosimeters. The results showed that the irradiation process slightly affected the mechanical parameters of the scaffold; however, it did not modify its crystallinity or thermal properties. The irradiation was uniform, since the measured uncertainty was low. The scaffold was pathogen-free after 7 days; this meant sterilization was achieved. These results indicated that gamma-sterilized scaffolds were a promising material for use as a skeletal muscle analog material for tissue-engineering applications because they can be sterilized with gamma rays without changing their chemical structure and mechanical properties. This study provided the dose distribution measurement and uncertainty calculations for the sterilization procedure.

Polyvinyl Alcohol-Chitosan Scaffold for Tissue Engineering and Regenerative Medicine Application: A Review

“…In addition, these scaffolds must be sterilized before being used in medical and clinical applications. Some sterilization methods may affect the mechanical and chemical properties of the scaffold [ 121 ].…”

“…Although PVA-CS was shown to be biocompatible [18], further studies are needed to evaluate its long-term safety and efficacy in vivo. Some sterilization methods may affect the mechanical and chemical properties of the scaffold [121]. PVA-CS nanoparticles are pH-dependent [98], which means that their physicochemical properties change with the change in pH.…”

Muscle-like Scaffolds for Biomechanical Stimulation in a Custom-Built Bioreactor

“…The initial length of the scaffold was 17 mm for the mobile grip and for the control grip. After the scaffold was assembled on the grips, they were sterilized using 25 kGy of gamma rays in a An Ob-Servo Ignis with a Co-60 source gamma irradiator (Izotop, Budapest, Hungary) [42]. For each replica, a new scaffold was assembled and sterilized prior to its use.…”

The Impacts of the Sterilization Method and the Electrospinning Conditions of Nanofibrous Biodegradable Layers on Their Degradation and Hemocompatibility Behavior

“…EO (chemical) sterilization is particularly effective at low temperatures; however, this method entails the risk of chemical modification of the polymer, which could lead to changes in the mechanical properties, degradation behavior, and biocompatibility [ 26 , 27 , 29 ]. Although ionizing gamma irradiation sterilization is a very effective sterilization method (including for SARS-CoV-2 [ 30 ]), changes in the covalent structure of the polymer (the crosslinking of macromolecules and the cleavage of bonds) may lead to changes in the resulting properties of the polymer [ 24 , 31 , 32 , 33 ].…”