Processamento de fios de quitosana em telas para aplicações biomédicas.

Abstract

The objective of this work was to develop meshes from the weaving of monofilament and multifilaments chitosan threads obtained by wet spinning for possible biomedical applications. In addition, wet spinning process steps have been optimized to obtain fibers with mechanical properties suitable for the weaving process. For the wet spinning process 4% chitosan solution (w / v) and coagulation bath containing 70% (0.5M) sodium hydroxide/30% methanol were used. Fiber coagulation kinetics was evaluated by Optical Microscopy (OM); The drying methodology was evaluated by Thermogravimetric Analysis (TGA), X-ray Diffractometry (XRD) and tensile test. The ideal coagulation time was determined and the drying methodology was efficient. From the results of tensile and XRD, it was chosen for the condition of drying of the wires under tension. The monofilament and multifilaments wires obtained were characterized by tensile test and Scanning Electron Microscopy (SEM). The configuration of the yarn affected its mechanical properties. Moreover, it was verified from the morphological tests that the yarns preserve the characteristics of the individual filaments present the typical microstructure of fibers obtained by wet spinning. The woven meshes obtained were evaluated by OM, tensile test, swelling degree, in vitro enzymatic biodegradation and in vitro cytotoxicity. From the tensile and OM tests it was decided to coat with a 1,5% chitosan solution (w / v). The woven mesh obtained from the tri-filament yarns withstood higher loads. The tensile strength of the samples in the wet state was similar to the human dermis. The configuration of the yarn used in weaving directly influenced the amount of water absorbed and the enzymatic degradation kinetics of the fabrics. The results of the in vitro cytotoxicity test showed that the samples showed no cytotoxicity and were classified as satisfactory. Thus, chitosan woven mesh with good mechanical, biodegradable and biocompatible properties were obtained, with potential for biomedical applications, such as bioactive dressings, tissue engineering grafts, soft tissue reinforcement or even as a controlled drug release system.