Effect of electrospun poly(D,L‐lactide) fibrous scaffold with nanoporous surface on attachment of porcine esophageal epithelial cells and protein adsorption

Abstract

Electrospun scaffolds have been increasingly used in tissue engineering applications due to their size-scale similarities with native extracellular matrices. Their inherent fibrous features may be important in promoting cell attachment and proliferation on the scaffolds. In this study, we explore the technique of fabricating electrospun fibers with nano-sized porous surfaces and investigate their effects on the attachment of porcine esophageal epithelial cells (PEECs). Porosity was introduced in electrospun poly(D,L-lactide) fibers by creating vapor-induced phase separation conditions during electrospinning. The nanoporous fiber scaffolds were mechanically weaker than the conventional solid fiber scaffolds and solvent-cast films of the same polymer. However, the nanoporosity of the fibers was found to enhance the levels of adsorbed protein from a dilute solution of fetal bovine serum. The amount of protein adsorbed by nanoporous fiber scaffolds was approximately 80% higher than the solid fiber scaffolds. This corresponds to an estimated 62% increase in surface area of the porous fibers than the solid fibers. By comparison, the solvent-cast films adsorbed low levels of protein from the FBS solution. In addition, the porous fibers were found to be advantageous in enhancing initial cell attachment as compared with the solid fibers and solvent-cast films. It was observed that nanoporous fiber scaffolds seeded with PEECs had significantly greater number of viable cells attached than the solid fiber scaffolds after 10 and 24 h in culture. Hence, our results indicate that nanosized porous surfaces on electrospun fibers enhance both protein adsorption and cell attachment. These findings provide a method to improve cell-matrix interactions of electrospun scaffolds for tissue engineering applications.

A nanoporous surface is essential for glomerular podocyte differentiation in three-dimensional culture

“…In this sense, podocytes, despite the presence of numerous ramifications, display a similar behavior to that of other epithelial cell types whose attachment and spreading seem to be discouraged by rough surfaces 47,48 and facilitated instead by nanoporous materials. 49 This behavior was not unexpected as it indirectly confirms what is known about the geometry of the GBM surface obtained by SEM studies performed after freeze-fracture procedures optimized to get a view of the GBM itself. From these analyses, the GBM appears indeed porous, which is required for the primary filtering function of the glomerular capillary.…”

Tuning electrospinning parameters for production of 3D-fiber-fleeces with increased porosity for soft tissue engineering applications

“…However, when scaffolds were produced with larger porosity increased cell infiltration in vitro and in vivo was observed (Leong et al, 2009). For these reasons DP-and PLGA-scaffolds with increased porosity were produced by co-electrospinning with various ratios of water-soluble PEG that could be removed easily.…”

“…Many applications are related to the biomedical field. Particularly, electrospun polymeric fibers were employed for the production of scaffolds for vascular tissue engineering (Boland et al, 2004;Sell et al, 2009;McClure et al, 2011) or hollow organ substitutes such as bladder, trachea and esophagus (Baker et al, 2006;Chen et al, 2006;Brizzola et al, 2009;Leong et al, 2009). Although requirements for medical scaffolds are numerous and vary with every application, some of them are fulfilled by the processing technique itself (Mano et al, 2007).…”

“…Lack of pore interconnectivity of electrospun fiber scaffolds is a major drawback of the technique, since the scaffolds are very dense allowing only poor cell infiltration and tissue ingrowths. Recently, several solutions have been proposed; among those, cryoelectrospinning using ice-crystals as templates for enlarged pore formation leading to better cell infiltration in vitro and in vivo Leong et al, 2009). However, the technique has some limitations, as the controllability and homogeneity of the pore size are difficult to achieve .…”

Heparinized nanohydroxyapatite/collagen granules for controlled release of vancomycin

“…Microporosity is known to result in higher surface area that induces protein adsorption, ion exchange, and bone-like apatite formation. 28 The presence of nanoporosity also improves protein adsorption and enhances initial cell attachment 29 because of the large surface-to-volume ratio. 9 Using micro-CT, it was only possible to assess microporosity, as the equipment does not have enough resolution to determine nanoporosity.…”