Prevention of Postsurgical Abdominal Adhesion Using Electrospun TPU Nanofibers in Rat Model

Abstract

Intra-abdominal adhesions following surgery are a challenging problem in surgical practice. This study fabricated different thermoplastic polyurethane (TPU) nanofibers with different average diameters using the electrospinning method. The conditions were evaluated by scanning electron microscopy (SEM), atomic force microscope (AFM), and Fourier transform infrared spectrometer (FTIR) analysis. A static tensile test was applied using a strength testing device to assess the mechanical properties of the electrospun scaffolds. By changing the effective electrospinning parameters, the best quality of nanofibers could be achieved with the lowest bead numbers. The electrospun nanofibers were evaluated in vivo using a rat cecal abrasion model. The macroscopic evaluation and the microscopic study, including the degree of adhesion and inflammation, were investigated after three and five weeks. The resultant electrospun TPU nanofibers had diameters ranging from about 200 to 1000 nm. The diameters and morphology of the nanofibers were significantly affected by the concentration of polymer. Uniform TPU nanofibers without beads could be prepared by electrospinning through reasonable control of the process concentration. These nanofibers’ biodegradability and antibacterial properties were investigated by weight loss measurement and microdilution methods, respectively. The purpose of this study was to provide electrospun nanofibers having biodegradability and antibacterial properties that prevent any adhesions or inflammation after pelvic and abdominal surgeries. The in vivo experiments revealed that electrospun TPU nanofibers reduced the degree of abdominal adhesions. The histopathological study confirmed only a small extent of inflammatory cell infiltration in the 8% and 10% TPU. Conclusively, nanofibers containing 8% TPU significantly decreased the incidence and severity of postsurgical adhesions, and it is expected to be used in clinical applications in the future.

Antiadhesive Nanofibrous Materials for Medicine: Preventing Undesirable Tissue Adhesions

“…Last, but not least, in vivo experiments bring the most valuable outcomes. Some of the studies are performed on small animals, such as rats or mice. ,,,− ,,, Tendon and epidural antiadhesion/adhesion properties were mostly tested on rabbit animal models, as in studies. ,, Utilization of higher animals for the assessment of antiadhesive properties in abdominal surgeries was reported in our previous studies. − …”

“…The PLGA membrane had the lowest degree of inflammation compared to all other groups and showed the best antiadhesive results. 16 Gholami et al 17 introduced nanofibrous membranes based on polyurethane (PU). Medical-grade polyurethane was dissolved in tetrahydrofuran and N,N-dimethylformamide in different concentrations (6, 8, 10, and 12% w/v).…”

“…The study further investigated the degradation rates on the developed materials; the weight loss reached 86.23% by day 64 for the 8% PU nanofiber, meaning a faster degradation rate compared to the commercial surgical mesh. 17 Our team investigated PCL and poly(L-lactide-co-ε-caprolactone) (PLCL) nanofibrous materials fabricated via the needleless electrospinning technique Nanospider. The homogeneous layers were sterilized via low-temperature ethylene oxide and applied in the size 2 × 5 cm to intestinal anastomoses during a large animal in vivo experiment.…”

“…The best adhesion inhibition score was reached by using the 8% polyurethane nanofibers. The study further investigated the degradation rates on the developed materials; the weight loss reached 86.23% by day 64 for the 8% PU nanofiber, meaning a faster degradation rate compared to the commercial surgical mesh …”

In Vivo Stable Allogenic Cartilage Regeneration in a Goat Model Based on Immunoisolation Strategy Using Electrospun Semipermeable Membranes

“…As a biocompatible inert material ap-proved by the U.S. Food and Drug Administration, thermoplastic polyurethane (TPU) has been widely used to prepare electrospun membranes because of its inherent nonimmunogenic and non-degradable characteristics. [20] The main disadvantage of TPU electrospun membranes as an immunoisolation SPM is the lack of hydrophilicity, which hinders nutrient exchange. [21,22] The hybrid synthetic-natural electrospinning strategy of combining biocompatible gelatin (GT) with a synthetic polymer has been verified to efficiently modify hydrophilicity of polymers.…”