Physical and mechanical characterizations of oxidized regenerated cellulose/polycaprolactone composite for use as a synthetic dura mater

An inadequate dural closure is one of the most challenging problems for neurosurgeons during the surgical procedures. A repair of the dura mater by natural or synthetic materials is often needed. This should satisfy fundamental criteria for example preventing cerebrospinal fluid leakage, exhibiting similar mechanical properties to the natural dura mater and not inducing foreign body reaction or inflammation. Oxidized regenerated cellulose (ORC) and polycaprolactone (PCL) have been extensively used as hemostatic agent and implant in many biomedical applications due to their long term proven safety, biodegradability and biocompatibility. This study investigated the potential of using a combination of ORC and PCL as a novel dural substitute. ORC/PCL composites were prepared by solution infiltration of ORC sheet with PCL solution (Mw ≈ 80,000) at various concentrations ranging 10-50 g/100 ml. Characterizations including density, tensile properties and microstructure were then performed. It was found that the density of all formulations did not differ and were in the range of 0.5-0.6 kg m^-3. Microstructure of the samples typically comprised a bilayer structure having a PCL layer on one side and the ORC/PCL mixed layer on another side. Tensile modulus and strength initially decreased with increasing PCL concentration for up to 20% and re-increased again with further increasing PCL concentration. Elongation at break of all formulations was not significantly different. Both physical and mechanical properties of the samples were found to be similar to those of natural human dura mater.