Formation of Three-Dimensional Polysuccinimide Electrospun Fiber Meshes Induced by The Combination of CaCl 2 and Humidity.

Even though electrospinning is getting more and more attention, the preparation of three-dimensional (3D) nanofibrous meshes is still a big challenge that limits the application of electrospun materials, especially in tissue engineering. To overcome this problem several solutions have been introduced but most of them focus on the postprocessing of the electrospun meshes. In this paper, we present a straightforward novel method that utilizes the joint effect of the addition of CaCl 2 and the relative environmental humidity (RH), which can induce the random 3D formation of polysuccinimide (PSI) electrospun fibers with different such as wrinkled or ribbon-like structures. Although the effect of humidity and inorganic salt additives on the micro- and macrostructure of electrospun fibers is known, the connection between the two in this manner has never been presented. To investigate the effect, fibers with different PSI and CaCl 2 concentrations at different humidity RH levels were prepared, and their microstructure was visualized with high-resolution scanning electron microscopy (SEM). To reveal the nature of the interaction between the polymer and the CaCl 2 Fourier-transformed infrared (FTIR), X-ray diffraction (XRD), and thermogravimetry (TGA) measurements were carried out and 3D nanofibrous structures were obtained. This article is protected by copyright. All rights reserved.