**5. Potential applications of electrospun PU nanofibers**

PU nanofibers prepared by electrospinning technology may have almost circular cross-sections, smooth surfaces, and diameters ranging from a few nanometers to several micrometers. Electrospun nanofibers have great applicability for drug delivery applications [16, 96–101], medical implants [102], nanocomposites for dental restoration [103], preservation of bioactive agents [104, 105], tissue engineering [12, 106], wound dressing [21, 43, 82], biosensors [107, 108], molecular separation [109], filters [45, 110, 111], and protective clothing [112–114]. Potential applications of electrospun PU nanofibers are discussed in depth below.
