3D Microporous Scaffolds Manufactured via Combination of Fused Filament Fabrication and Direct Laser Writing Ablation

Abstract

A 3D printing fused filament fabrication (FFF) approach has been implemented for the creation of microstructures having an internal 3D microstructure geometry. These objects were produced without any sacrificial structures or additional support materials, just by precisely tuning the nozzle heating, fan cooling and translation velocity parameters. The manufactured microporous structures out of polylactic acid (PLA) had fully controllable Micromachines 2014, 5 840 porosity (20%-60%) and consisted of desired volume pores (∼0.056 µm 3 ). The prepared scaffolds showed biocompatibility and were suitable for the primary stem cell growth. In addition, direct laser writing (DLW) ablation was employed to modify the surfaces of the PLA structures, drill holes, as well as shape the outer geometries of the created objects. The proposed combination of FFF printing with DLW offers successful fabrication of 3D microporous structures with functionalization capabilities, such as the modification of surfaces, the generation of grooves and microholes and cutting out precisely shaped structures (micro-arrows, micro-gears). The produced structures could serve as biomedical templates for cell culturing, as well as biodegradable implants for tissue engineering. The additional micro-architecture is important in connection with the cell types used for the intention of cell growing. Moreover, we show that surface roughness can be modified at the nanoscale by immersion into an acetone bath, thus increasing the hydrophilicity. The approach is not limited to biomedical applications, it could be employed for the manufacturing of bioresorbable 3D microfluidic and micromechanic structures.

3D microfabrication of complex structures for biomedical applications via combination of subtractive/additive direct laser writing and 3D printing

“…Material -PLA Additive fabrication via multiphoton absorption opens the possibility to produce complex true 3D microstructures with feature size as small as hundreds of nm [1]. Furthermore, composite manufacturing combining different materials in distinct parts of the structure can be realized this way [2]. Here we show that these capabilities can be used for the creation of 3D biomedical microobjects complex both in their architecture (Fig.…”

“…(b) -enhanced topography of a 3DP scaffold via sharp focusing cutting [2]. Material -PLA Additive fabrication via multiphoton absorption opens the possibility to produce complex true 3D microstructures with feature size as small as hundreds of nm [1].…”

“…Details on these systems can be found in [4] and [5] respectively. Polymers used for the creation of the structures include but are not limited to hybrid organic-inorganic photopolymers (namely SZ2080), polylactic acid (PLA) and PEG-DA [2], including their formulation doped with metallic nanoparticles. Additionally two types of 3DP were tested.…”

“…This enables combining a wide array of materials as well as freeform 3D geometry best suited for any given task. What is more, efficiency can be further enhanced by coupling laser fabrication with conventional 3D printing (3DP) technologies [2]. In such case fast 3DP is employed for the creation of the base structure, while the laser is used to further decorate it with fine features (from tens of µm to hundreds of nm [1]) that cannot be produced using 3D printing [2].…”

“…What is more, efficiency can be further enhanced by coupling laser fabrication with conventional 3D printing (3DP) technologies [2]. In such case fast 3DP is employed for the creation of the base structure, while the laser is used to further decorate it with fine features (from tens of µm to hundreds of nm [1]) that cannot be produced using 3D printing [2]. Here we will discuss current progress on the aforementioned approach of combining subtractive and additive DLW with 3DP for the creation of structures that could be used in biomedical applications.…”