Fabrication and applications of alginate-based micro-and nanofibers

Development on fabrication techniques for producing alginate-based micro- and nanofibers is still a challenging task for researchers. Conventional alginate-based fibers having diameters in the range of tens to hundreds microns have been manufactured by a traditional wet-spinning process. Versatile classes of materials are incorporated into the alginate fibers in order to improve the properties of the fibers for the application in medical area as well as to generate fibers for new classes of applications. To avoid gelation problem caused by complexation via ionic interactions between alginate and chitosan, several means are proposed and distinguished/outstanding properties of the alginate/chitosan hybrid fibers can be obtained. Electrospinning is another effective and simple technique for producing ultra-fine alginate-based fibers with high aspect ratio and high specific surface area. While the ease of fabrication of alginate by wet spinning leads the alginate to play an important role in the processability of the hybrid fibers, study on processability of the alginate-based electrospun fibers still under observation and can be classified into different categories depending on various parameters. This chapter aims to give an overview of utilizing the wet spinning and the electrospinning processes to fabricate alginate-based micro- and nanofibers. The principles and drawbacks of each fabrication technique will be discussed. Strategies to overcome the limitations which will lead to the forthcoming technology in the production of a wide variety of alginate-based fibers as well as the applications will be summarized.