Sterilized hollow-fiber membranes are used in hemodialysis, ultrafiltration, bioprocessing, and tissue engineering applications that require a stable and biocompatible surface. In this study, we demonstrated significant changes in the fiber physicochemical properties with different methods of sterilization. Commercial polysulfone (PS) hollow fibers containing poly(vinyl pyrrolidone) were subjected to standard ethylene oxide (ETO), sodium hypochlorite (bleach), and electron-beam (e-beam) sterilization techniques followed by analysis of the surface hydrophilicity, morphology, and water-retention ability. E-beam sterilization rendered more hydrophilic fibers with water contact angles near 47 degrees compared to the ETO-and bleach-treated fibers, which were each near 56 degrees. Atomic force microscopy revealed lumen root mean square (rms) roughness values near 19 nm for all three sterilization methods; however, e-beam-sterilized and bleach-treated fibers had significantly higher (similar to 106 nm) rms values for the outer wall compared to the ETO-sterilized fibers (similar to 39 nm). The increased hydrophilicity and surface area of the e-beam-sterilized fiber were reflected by a greater water evaporation rate than that of the ETO- treated fiber. These results demonstrate that common sterilization methods may significantly and distinctly alter the polymer membrane physicochemical properties, which may, in turn, impact the performance and, in particular, surface fouling. For tissue engineering and bioprocessing applications, these changes may be leveraged to promote cell adhesion and spreading. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 3429-3436, 2011