RESUMEN
Nerve guidance conduits (NGCs) have been widely accepted as a promising strategy for peripheral nerve regeneration. Fabricating ideal NGCs with good biocompatibility, biodegradability, permeability, appropriate mechanical properties (space maintenance, suturing performance, etc.), and oriented topographic cues is still current research focus. From the perspective of translation, the technique stability and scalability are also an important consideration for industrial production. Recently, blow-spinning technique shows great potentials in nanofibrous scaffolds fabrication, possessing high quality, high fiber production rates, low cost, ease of maintenance, and high reliability. In this study, we proposed for the first time the preparation of a novel NGC via blow-spinning technique to obtain optimized performances and high productivity. A new collagen nanofibrous neuro-tube with the bilayered design was developed, incorporating inner oriented and outer random topographical cues. The bilayer structure enhances the mechanical properties of the conduit in dry and wet, displaying good radial support and suturing performance. The porous nature of the blow-spun collagen membrane enables good nutrient delivery and metabolism. The in vitro and in vivo evaluations indicated the bilayer-structure conduit could promoted Schwann cells growth, neurotrophic factors secretion, and axonal regeneration and motor functional recovery in rat.
RESUMEN
A novel bioflocculant (BW-P3) was produced by a strain of Enterobacter sp. P3 using brewery wastewater as substrate and was further applied to remove the colored substance of fracturing flowback water. The optimum conditions for bioflocculant production were specified by the response surface methodology as COD of brewery wastewater 1487.77 mg/L, glucose 8.94 g/L and initial pH 7.09, under which a bioflocculant yield of 1.274 g/L could be reached. The BW-P3 consists of 79.12% polysaccharides and 15.63% protein. Results show that BW-P3 has a high molecular weight (921 kDa) and contains functional groups (hydroxyl, amino, carbonyl, and acylamino) that likely contribute to flocculation. When using the BW-P3 to flocculate fracturing flowback water, the optimal dosage was 1 g/L BW-P3 with addition of 100 mg/L polymeric aluminum chloride as coagulant aid, and treated under 50 °C at pH 7. Under the optimal condition, the removal rates of chroma and suspended solids (SS) of the fracturing flowback water could reach 85% and 52%, respectively.
