Electrospraying poloxamer/(bio-)polymer blends using a needleless electrospinning machine

Electrospinning can be used to create nanofiber mats with high material purity and a large inner surface, applicable for medical or biotechnological filters, cell growth, and so on. Not each polymer which can be dissolved, however, can be spun in this way. Depending on the material, solution, and spinning parameters, especially on the molecular weight and the polymer concentration in the solution, either fibers or droplets can be formed. Both fibers and droplets are of technological interest for different applications. This article examines the possibilities of electrospinning or electrospraying poloxamer 188 (formerly known as Lutrol F 68, BASF, Germany) in combination with different biopolymers (dextran, gelatin, and agarose) as well as polyacrylonitrile (PAN) which belongs to the polymers spinnable from nontoxic solvents. Due to the similarity of the chemical structures of poloxamer and poly(ethylene glycol), a well-known spinning agent, and the relatively low molecular weight of poloxamer 188, it can be expected to work as a spraying agent. Our results show that electrospraying poloxamer/biopolymer blends is indeed possible, with the unexpected effect that for higher polymer concentrations, combining poloxamer 188 with dextran, fibers are formed additionally on parts of the substrate. Co-spinning poloxamer 188 with PAN, on the other hand, results in creation of a nanofiber mat whose morphology is mainly defined by the PAN content. The study shows that poloxamer can indeed be used as a spraying/spinning agent in electrospraying/electrospinning diverse biopolymers.