Continuous wet spinning and dug-loaded wet-spun fibers

Abstract

Wet spinning is a simple technique and may be used to produce fibrous biomedical products. However, continuous wet spinning to make structures with aligned fibers is not easy and requires detailed investigations. In wet spinning itself, several parameters (polymer, polymer solution concentration, spinneret inner diameter, fiber drawing speed, coagulation bath, etc.) have major influences on the fibrous products. For biomedical applications, wet-spun fibers may serve as delivery vehicles for biomolecules such as drugs. In the current work, an apparatus was designed and constructed for the continuous wet spinning of biomedical polymers such as sodium alginate (SA). Working without fiber drawing by simple injecting a polymer solution into the coagulation bath, non-woven fibers could be obtained; working at a sufficient drawing speed, aligned fibers could be made and collected on a mandrel. For investigating wet spinning of drug-loaded fibers, SA and fluorouracil (5-FU, an anticancer drug) were used in the current study. SA solutions of different concentrations and also different drug concentrations were used to make wet-spun fibers. Subsequently, in vitro release tests were conducted to study drug release from fibers. It was shown that the SA solution concentration had significant effects on the morphology and diameter of wet-spun SA fibers and consequently the release behavior of 5-FU from these fibers.