Polycaprolactone Scaffolds Fabricated with an Advanced Electrohydrodynamic Direct-Printing Method for Bone Tissue Regeneration

Abstract

Electrohydrodynamic (EHD) direct writing has been used in diverse microelectromechanical systems and various supplemental methods for biotechnology and electronics. In this work, we expanded the use of EHD-induced direct writing to fabricate 3D biomedical scaffolds designed as porous structures for bone tissue engineering. To prepare the scaffolds, we modified a grounded target used in conventional EHD direct printing using a poly(ethylene oxide) solution bath, elastically cushioning the plotted struts to prevent crumbling. The fabricated scaffolds were assessed for not only physical properties including surface roughness and water uptake ability but also biological capabilities by culturing osteoblast-like cells (MG63) for the EHD-plotted polycaprolactone (PCL) scaffold. The EHD-scaffolds showed significantly roughened surface and enhanced water-absorption ability (400% increase) compared with the pure rapid-prototyped PCL. The results of cell viability, alkaline phosphatase activity, and mineralization analyses showed significantly enhanced biological properties of the scaffold (20 times the cell viability and 6 times the mineralization) compared with the scaffolds fabricated using RP technology. Because of the results, the modified EHD direct-writing process can be a promising method for fabricating 3D biomedical scaffolds in tissue engineering.

Control of cell growth on 3D‐printed cell culture platforms for tissue engineering

“…Many different techniques have been developed in the recent years to build cell culture platforms and scaffolds for tissue engineering, including selective laser sintering, stereo lithography, fused filament fabrication, microfabrication, phase separation, electrospinning and 3D printing . Electro‐hydrodynamic jet (E‐jet) printing is a new high‐resolution printing method whereby the geometric feature of the built scaffolds can be precisely controlled using a broad range of materials . E‐jet printing is a nano‐manufacturing process, whereby the printing materials, such as polymer solutions or polymer melt, are induced using an electric field to form a fine jet much smaller than the nozzle diameter, overcoming the limitations imposed by nozzle size, thus producing micro‐ to nano‐scale features.…”

“…In this research, we applied the E‐jet printing technique to construct different 2D and 3D cell culture platforms with defined structures . We used poly‐lactic‐co‐glycolic acid (PLGA) as the construction polymer for the platforms due to its high viscosity and low conductivity .…”

Fiber-based tissue engineering: Progress, challenges, and opportunities

“…The scaffolds fabricated by direct writing method showed a higher mechanical strength compared to those produced by repetition of writing and elecrospinning. In another study, Ahn et al used two techniques, direct writing and combined direct writing/electrohydrodynamic spinning, to generate PCL scaffolds for bone tissue engineering and to compare the physical properties of resultant scaffolds (Ahn et al, 2011). The results showed that the latter resulted in a more porous structure while the structures achieved by the former technique were stronger.…”

The interfacial pH of acidic degradable polymeric biomaterials and its effects on osteoblast behavior

“…Accordingly, it has attracted much interest to accurately deliver, transport, fasten and functionalize osteoblasts by seeding on specific surfaces to stimulate bone formation, including ceramics 4 , polymers 5, 6 and metals 7 . It is reported that the acid-base equilibrium plays an important role in influencing the behavior of osteoblasts, and thus affects the bone remodeling process 8–11 .…”

“…Most notably, polyester-based polymers, such as polylactide (PLA) 22 , polyglycolide (PGA) 24 , and polycaprolactone (PCL) 5 , are widely used as bone substitutes due to their good biocompatibility, ease of processing, appropriate mechanical properties, and biodegradability. However, the release of acidic products may acidify the microenvironment and thus lower the local pH, although this is thought to be buffered by the blood.…”