Enhancing the mechanical and degradation properties of PGA/TMC copolymer sutures for surgical applications by annealing

Abstract Surgeons often hesitate to utilize absorbable sutures in adults due to concerns about suture line breakage, which can lead to aneurysmal formation. The annealing process was employed to improve the physical properties of PGA/TMC copolymer sutures, enhancing their mechanical properties for safer use in adult vascular surgery. The trade name of the PGA/TMC copolymer suture is Maxon. In vitro degradation studies were conducted to assess the impact of the annealing process on the mechanical properties and degradation rate of both untreated and annealed samples at 100 °C, 120 °C, and 140 °C for 2 h. A Mach–Zehnder interferometer, coupled with a mechanical device, was used to determine optomechanical properties and 3D refractive index profiles for the Maxon samples. X-ray diffraction, Fourier-transform infrared spectroscopy, and optical microscopy were employed to measure structural variations in the samples due to annealing and in vitro degradation. The results showed that the annealed sample at 100 °C retained 69 % of its original mechanical strength after 32 days of degradation, compared to 51 % for the untreated sample, demonstrating a 35 % improvement in degradation resistance. This indicates that the annealed sample exhibited improved mechanical stability and degradation resistance, making it more suitable for vascular surgical applications.