The present study described a new method with one step to fabricate silk fibroin nano- and microspheres, with the size of spheres and crystalline structure being controllable during processing. Polyethylene glycol, a type of synthetic polymer that is widely used in the pharmaceutical industry as a formulation excipient, was utilized to induce silk fibroin to self-assemble into nano- and microspheres. The addition of a certain amount of salt in the blending solution with subsequent titration into ethanol could improve the size dispersion, yield, and crystalline β-sheet structure (silk II) compared to those prepared without salt addition during preparation. Silk microspheres prepared in the presence of salts were less porous and more homogeneous in size than those prepared in the absence of salts. The present study described a new method with one step to fabricate silk fibroin nano- and microspheres, with the size of spheres and crystalline structure being controllable during processing. Silk microspheres prepared in the presence of salts were less porous and more homogeneous in size than those prepared in the absence of salts (Control). These properties are important not only for the stabilization of particles but also for the controlled release of entrapped drug molecules.

中文翻译：

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丝绸纳米和微球的一步制备和表征

本研究描述了一种单步制造丝素蛋白纳米球和微球的新方法，在加工过程中球的大小和晶体结构是可控的。聚乙二醇是一种在制药工业中广泛用作制剂赋形剂的合成聚合物，用于诱导丝素蛋白自组装成纳米和微球。与在制备过程中不加盐的情况相比，在混合溶液中加入一定量的盐，随后滴定到乙醇中，可以改善尺寸分散、产率和结晶 β-折叠结构（丝 II）。与在不存在盐的情况下制备的丝微球相比，在盐存在下制备的丝微球孔隙更少，尺寸更均匀。本研究描述了一种单步制造丝素蛋白纳米球和微球的新方法，在加工过程中球的大小和晶体结构是可控的。在盐存在下制备的丝微球与在不存在盐的情况下制备的丝微球相比（对照）孔隙更少且尺寸更均匀。这些特性不仅对于稳定颗粒很重要，而且对于包埋药物分子的控制释放也很重要。