仿生制备的再生丝素蛋白水溶液的静电纺丝(Ⅲ)-金属离子的影响

Electrospinning of biomimetic regenerated silk fibroin aqueous solutions-part 3:the effect of metallic ions

通过添加在家蚕丝腺体中含量较多的钾、钙、镁3种金属离子，研究了不同种类的金属离子对丝素蛋白水溶液的流变性能及静电纺丝的影响。研究结果表明，添加K^＋后溶液的表观粘度较大，而含Ca^2＋和Mg^2＋的丝素溶液粘度较小；分别加入0．225mol／L K^＋、Ca^2＋和Mg^2＋后，再生丝素蛋白水溶液在PH为6．0浓度为30％时都可通过静电纺丝法成纤。对于添加了0．225mol／L的混合金属离子的PH为6．0的再生丝素蛋白水溶液而言，丝素溶液的静电纺丝可纺浓度在27％～35％之间，随着丝素浓度的增加，所制纤维的平均直径增大，直径分布变宽。通过拉曼光谱、X衍射、DSC对再生丝素蛋白纤维的结构进行了表征，发现再生丝素蛋白纤维中已含有少量的Silk Ⅱ结构，主要是无定形结构。

In this paper,the effects of K^＋ ,Ca^2＋ , Mg^2＋ which had higher concentrations in the grand ot the bombyx mori silkworm on rheological and electrospinning properties of regenerated silk fibroin （RSF） aqueous solutions were investigated. It was found that RSF aqueous solution added with K^＋ appeared the higher apparent viscosity and the solutions with Ca^2＋ or Mg^2＋ appeared the lower viscosity under the same amount of K^＋ ,Mg^2＋ and Ca^2＋ ;by adding 0. 225mol/L K^＋ ,Ca^2＋ and Mg^2＋ to RSF aqueous solution at a pH of 6.0 with a concentration of 30% ,respectively,the electrospun fibers could be obtained. For adding 0. 225mol/L mixed metallic ions to RSF aqueous solution at a pH of 6.0,the electrospinnable concentration of RSF aqueous solutions were between 27% and 35%. With the increasing of concentration of RSF aqueous solutions, the average diameter of the electrospun silk fibers increased and the diameter distribution of that became wider. The structure of the electrospun fibers were characterized by FT-IR, XRD and DSC. It was found that the electrospun fibers had already involved a few silk Ⅱ structure although basically it was amorphous structure.