Electrospun fibers based on porcine plasma: a rheological and morphological study

The present work focuses on the assessment of the ability of porcine plasma protein (PPP) to be electrospun satisfactorily to form fibre mats, and their rheological and morphological characterization. Porcine plasma is a by-product of meat industry that is produced in an amount much larger than the market's demand, resulting in a surplus. Thus, its revalorization through the development of innovative membranes with several applications (e.g., biomaterials and agricultural) would help to alleviate the environmental issue associated with its landfill. PPP solutions possess a relatively high conductivity, due to the abundance of polar residues (e.g., aspartic and glutamic acid) on its molecular structure, which may be a positive aspect in the electrospinning process. As no fibres can be obtained from a PPP single solution due to its very low viscosity (~ 8.5 mPa·s), polyvinyl alcohol (PVA) was considered for the preparation of mixed PPP + PVA solutions. Different PVA and PPP contents were used, ranging from 4 to 7% w/w and 2 to 8% w/w, respectively. All electrospinnable mixtures displayed pseudoplasticity (flow indexes, n ~ 0.88), compared to the Newtonian behaviour of the single systems (n = 1). Mixed solutions keeping PVA content at 7% w/w could form electrospun composite membranes without significant imperfections (e.g., beads). Those composites showed larger nanofiber diameters as PPP content increased from 2% w/w (~ 310 nm) to 8% w/w (~ 540 nm). Considering that both components are biodegradable, fibre mats here produced could be of high interest as eco-friendly materials.