Electrospinning nanoribbons of a bioengineered silk-elastin-like protein (SELP) from water

Electrospinning of a silk-elastin-like protein (SELP), a repeat sequence protein polymer (RSPP) from aqueous solution, is reported here. The electrospinning of SELP47K resulted in fibers with a uniform, ribbon-like morphology. The solution properties of SELP47K provide ideal conditions for electrospinning and resultant nanoribbons are demonstrated to form self-standing, non-woven fiber meshes. The mechanical properties of these meshes have also been evaluated, and the ultimate tensile strength was found to be 30.8 MPa with an average initial modulus of 0.88 GPa. Furthermore, the effect of electrospinning parameters, such as solution concentration, applied voltage, collecting distance, and rate of spinning, on the fiber dimensions and morphology are studied. Within the experimental matrix, the width of these nanoribbons is found to be between 25 nm and 1800 nm. The secondary structure of SELP47K nanoribbons is analyzed by FTIR and WAXD and the methanol treatment resulted in improvements in the crystalline β-sheet structure when compared to as spun electrospun nanoribbons.