In the last decade, electrospinning technology has attracted a huge attention as a convenient processing method for the fabrication of nanofibrous structures for a number of bio/nanotechnological applications. Plain, drug-loaded or surface modified electrospun nanofibers scaffolds for tissue engineering and drug delivery are among the most explored systems. Electrospun biopolymer matrices and pH-responsive nanofibrous membranes developed by Argentinean and German students under IDEAR exchange program (Friedrich-Alexander-Universität of Erlangen-Nuremberg and Universidad Nacional Mar del Plata), are presented.
Zein-based electrospun nanofibers were obtained using benign solvents. The electrospinnability conditions of zein, zein/poly(glycerol sebacate) (PGS) and zein/poly(epsilon-caprolactone) (PCL) blends were explored. Blending zein with synthetic polymers improved degradation behavior in aqueous environment and mechanical properties.
Soy protein isolated (SPI) and SPI/gelatin blends were successfully electrospun using poly(ethylene oxide) as polymer carrier. The obtained matrices were completely characterized. Furthermore, to avoid the solubility in water and to tailor their degradability, a cross-linking process by photopolymerization was performed.
Nitrofurazone (NFZ) loaded Eudragit® S100 (ES100) nanofibrous membranes were fabricated as pH-responsive targeted drug delivery systems for wound healing. The electrospinnability of different polymer solutions and the morphology of the resulting nanofibers were studied. Uniform drug-loaded nanofibers without beads were obtained. NFZ was efficiently loaded in the nanofibers. Evaluation of the NFZ release profiles was conducted in a range of pH (5.5 – 8). ES100 is no soluble at pH < 7 and intuitively it was expected that there is no drug release or only a very slow release under these conditions. However, the tests in acidic media revealed the release of certain NFZ in time. Indeed, at the pH of the healthy skin (pH=5.5), the NFZ release was low, but not negligible. Overall, the obtained analysis results demonstrate a high potential for site specific pH-sensitive electrospun drug delivery carriers as wound dressings, though more optimization is still required for fine tuning the dissolution rates in acidic media by manipulating the nanofibers architecture and structure.