| Electrospinning is a simple and cost-effective way to get fibers in micro- and nano-meters, currently, more than one hundred kinds of materials have been eletrospun into micro- and nano-meters fibers. Most of the published reports are about randomly nonwoven mat as far as today, some are about well-aligned electrospinning nanofibers, however, there were only several researches referring to continuous fibers bundles.Especially, the energy crisis has become more and more vital in today's world, and the sence of environment protection has been enhanced globally, biodegradable materials, particularly native biodegradable materials attracts worldspread attentions. In which, spider is one of the strongest known natural materials with high tensile strength and toughness, having very superior mechanical properties, other more, Polylactic acid (PLA) is the most promising one. Both PLA and spider silk are perfect biomaterials due to their biodegradability and biocompatibility, with the potential applications of artificial tendon, organism, tissue engineering scaffolds, wound dressing materials, sutures and so forth.In this paper, Spider silk and PLA was used as raw materials, continuous nanofibers'bundles was achieved by electrospinning. The main contents of this paper include the effects of electrospinning process parameters, post-twisting and post-drawing on the filament, and then their biodegradability and biocompatibility, the details are as follow: Investigation on a technique for electrospinning continuous filaments constructed of nano-scale fiber bundles: spider protein (Ornithoctonus huwenna spider silk) and PLA mixed solution was used as electrtospinning solution, five factors were taken into account in our experimental process, including PLLA / spidroin solution mass proportion, reeling temperature, solution flow rate, rotating speed, voltages, besides, the continuous electropsinning time was another important element, finally, we get the optimized electrospinning parameters: mass ration of 9wt% PLLA and 1wt% spidroin solution 7:3, solution flow rate 4ml/h, reeling temperature 150℃, voltage 14kv, and winding speed 105±5rpm. In these conditions, the yarn goes smoothly and steadily, the inter-fibers shows a high degree of arrengment, the boundle shows no shrinkage in water, however, has a low stress and high strain, the mechnical properties need to be improved.Effect of the post-twisting and post-drawn on the structure and properties of the fiber bundles: we investigated the effect of post-twisting and post-drawing on the morphology, mechnical properties and crystalline structure of nanofiber bundles. Twisting made the loose bundle compact, the stress between individual fibers re inforced, the mechanical properties was also improved, single filament increased by 36.98% at 2250T/m and double filament increased by 29.97% at 1500 T/m.Post-drawing had an obvious effect on the as-spun bundles, with the increasing of the drawing ratio, fiber diameter and the liner destiny of the filament decreased, and stress at break and initial modulus increased by 70% and 93% respectively at a drawing ratio of 1.6, besides, heat-drawing can improve the crystalline structure, make a higher crystalline degree.The biodegradability and biocompatibility of the nano-scale fiber bundles: the biodegradability in phosphate buffer solution and actinomyces enzyme biodegradable fluid was studied respectively. The results didn't show obvious effect, there was no clear degradable signal in the SEM image, after 90 days in phosphate buffer solution, only slight weight lose and stress lose could be observed, which was a little obvious when using actinomyces enzyme biodegradable fluid, with 15.28% stress lose after 5weeks.MTT method was used to investigate the cell biocompatibility of the electrospun filament, the result showed a good compatibility with big rat fibroblasts, also, the addition of spider protein enhanced the compatibility between cell and matrix material, cell activity degree: spider protein fiber mat>pure PLLA fiber mat>blank templet...
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