One-step fabrication of a tunable nanofibrous well insert via electrolyte-assisted electrospinning

The integration of the Transwell (R) assay with an electrospun nanofiber membrane shows a significant potential in chemotactic assays and co-culture models, but the complicated integration processes often limit its utilization. Here, we present a one-step fabrication process of a nanofibrous well insert by adopting electrolyte-assisted electrospinning, named ELES. The utilization of ELES, which introduced the electrolyte solution as a temporal collector, enabled the facilitation of not only the fabrication of a freestanding electrospun polycaprolactone (PCL) nanofiber on the bottom opening of a well insert wall but also the spontaneous integration between the nanofiber membrane and the well insert wall in a one-step process. The versatility of this approach was demonstrated by modulating the diameter of PCL nanofibers and thickness of the membrane. The indentation test revealed stable integration between the membrane and the well insert wall. The fabricated nanofibrous well inserts were confirmed as an in vitro cell culture platform with promising cell culture results of mouse brain endothelial cell line (bEnd. 3).