Evaluation of permeability and fluid wicking in woven fiber bone scaffolds

Research characterizing transport of nutrients and waste in tissue engineering scaffolds has led to the study of scaffold properties that contribute to permeability and porosity of the scaffold. Both permeability and porosity contribute to the transport properties of the scaffold; however, permeability relates to the degree to which pores are interconnected within the scaffold. This work evaluated permeability for woven polymer fiber scaffolds by modulating the following scaffold parameters: material combination, weave configuration, and fiber geometry. Materials tested were poly-l-lactide and poly-l-lactide-co-ɛ-caprolactone in various combinations. Plain and crowfoot weave configurations were compared, and grooved wicking fibers were compared with round cross-section fibers to study fiber geometry. A modification of the constant head hydraulic conductivity test was used in combination with a vertical wicking test to determine levels of permeability of the woven scaffolds. Results showed a significant effect on permeability for combinations of weave configuration, fiber geometry, and material combination. However, modulating fiber geometry demonstrated the most significant contribution to permeability. This result suggests the grooved wicking geometry may be used in scaffold development to regulate transport by selectively moving fluid away or toward the area of interest by capillary action. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 306-313, 2019.