Additive Manufacturing of Wet-Spun Polysulfone Medical Implants

Research on additive manufacturing (AM) of high-performancepolymersprovides novel materials and technologies for advanced applicationsin different sectors, such as aerospace and biomedical engineering.The present article is contextualized in this research trend by describinga novel AM protocol for processing a polysulfone (PSU)/N-methyl-2-pyrrolidone (NMP) solution into medical implant prototypes.In particular, an AM technique involving the patterned depositionof the PSU/NMP mixture in a coagulation bath was employed to fabricatePSU implants with different predefined shape, fiber diameter, andmacropore size. Scanning electron microscopy (SEM) analysis highlighteda fiber transversal cross-section morphology characterized by a denseexternal skin layer and an inner macroporous/microporous structure,as a consequence of the nonsolvent-induced polymer solidificationprocess. Physical-chemical and thermal characterization of the fabricatedsamples demonstrated that PSU processing did not affect its macromolecularstructure and glass-transition temperature, as well as that afterpost-processing PSU implants did not contain residual solvent or nonsolvent.Mechanical characterization showed that the developed PSU scaffoldtensile and compressive modulus could be changed by varying the macroporousarchitecture. In addition, PSU scaffolds supported the in vitro adhesionand proliferation of the BALB/3T3 clone A31 mouse embryo cell line.These findings encourage further research on the suitability of thedeveloped processing method for the fabrication of customized PSUimplants.