Effects of common sterilization methods on the structure and properties of poly(D,L lactic-co-glycolic acid) scaffolds.

While methods for the production of scaffolds with the appropriate mechanical properties and architecture for tissue engineering are attracting much attention, the effects of subsequent sterilization processes on the scaffold properties have often been overlooked. This study sought to determine the effects of sterilization with ethanol, peracetic acid, ultraviolet irradiation, and antibiotic solution on the structure of 50:50 (mol:mol) 65:35, and 85:15 poly(D,L-lactic-co-glycolic acid [PLGA]) flat-sheet and hollow-fiber scaffolds. All methods resulted in scaffold sterilization, but scanning electron microscopy revealed deformations to the scaffold surface for all treatments. The extent of surface damage increased with treatment duration. This was further investigated by measurement of pore sizes, water flux, breaking strain, and Young's modulus. External pore size and water flux was found to be increased by all treatments in the following order: ethanol (largest), antibiotics, ultraviolet light, and peracetic acid. Pore sizes were 0.25 to 0.17 microm and water flux ranged from 0.01 kg x m(-2) x s(-1) to 3.34 kg x m(-2) x s(-1). For all samples, the Young's modulus was 1.0 to 31.1 MPa and breaking strain was 1.2 to 2.4 MPa. The results of this study suggest that antibiotic treatment shows the most potential to sterilize PLGA hollow fibers for tissue engineering.