Electrospinning is a widely used technique to draw recalcitrant biopolymer solutions into micro to nanoscale materials in a simple and economical way. In previous works, raw biopolymeric materials such as cellulose and silk were always dissolved and blended in various volatile solvents directly for a long time before producing nanofibers using electrospinning technique. Ionic liquids have long been used as a non-volatile solvent for natural insoluble biopolymers. Compared to traditional organic solvents, ionic liquids can dissolve the biopolymers without altering the molecular weight of the biopolymer. Additionally, ionic liquids do not generate unwanted side reactions, and they are eco-friendlier because they can be reused. The focus for this preliminary research is the production and characterization of electrospun micro to nanoscale composite biomaterials that were first regenerated from ionic liquids such as 1 -ethyl-3-methylimidizolium acetate (EMIMAc) and various coagulation baths (EtOH or water baths). Various ratios of silk-cellulose biocomposite films regenerated from ionic liquids were used as the "raw" materials and dissolved/dispersed into Formic Acid-CaC12 solution quickly, in order to initiate electrospinning of silk-cellulose nanomaterials. Because of the variability of ionic liquids, the nanomaterials produced using this technique could have unique or tunable properties like enhanced mechanical properties, large surface area to volume ratios, and low structural defects. Compared to previous electrospinning techniques that use ionic liquids directly as solvents, this method also avoids complex washing procedures for nonvolatile ionic liquids during the high-voltage electrospinning process. FTIR and SEM data suggest that the structure and morphology of the final nanosized samples becomes more globular when the biopolymer composition ratio has increased silk content. Additionally, it was observed that the type of ionic liquid and coagulation bath used when generating the biofilms both affected the nanofiber production and morphology of the sample. This two-step electrospinning method, using ionic liquid as a non-volatile solvent to first create raw composite materials, may lead to extensive research into its biomedical and pharmaceutical technology applications in the future.
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