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.

a b s t r a c tAn important class of novel mesoporous and microporous adsorbents like metal-organic frameworks (MOFs) are normally produced in powder form. This paper presents a generic method of manufacturing and characterisation of these materials into low pressure drop and energy saving monolithic structures for industrial applications. One of the MOF candidates that was considered in this study was MIL-101 (Cr) ([Cr 3 O(OH)(H 2 O) 2 (bdc) 3 ].xH 2 O; bdc ¼ 1,4-benzenedicarboxylate), and the model contaminant gas tested was carbon dioxide (CO 2 ). MIL-101 (Cr) monoliths were manufactured by paste extrusion techniques from the synthesized MIL-101 (Cr) powder. These MIL-101 (Cr) monoliths were then characterised using powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), radial compression tests and intelligent gravimetric analysis (IGA). Adsorption properties of the prepared MIL-101 (Cr) powder and monoliths were determined from their pure CO 2 sorption isotherms and dynamic adsorption breakthrough curves, that were carried out using high concentration (40% v/v) CO 2 challenge. Results have demonstrated that the resulting MIL-101 (Cr) monoliths were highly porous, mechanically strong on compressive loading, thermally regenerable with comparable CO 2 adsorption capacity to the synthesized MIL-101 (Cr) powder. From breakthrough curves, mass transfer characteristics such as mass transfer zone velocity and length of the prepared MIL-101 (Cr) monoliths have also been evaluated in this study.

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