Towards excimer-laser-based stereolithography: a rapid process to fabricate rigid biodegradable photopolymer scaffolds

Abstract

We demonstrate high-resolution photocross-linking of biodegradable poly(propylene fumarate) (PPF) and diethyl fumarate (DEF) using UV excimer laser photocuring at 308 nm. The curing depth can be tuned in a micrometre range by adjusting the total energy dose (total fluence). Young's moduli of the scaffolds are found to be a few gigapascal, high enough to support bone formation. The results presented here demonstrate that the proposed technique is an excellent tool for the fabrication of stiff and biocompatible structures on a micrometre scale with defined patterns of high resolution in all three spatial dimensions. Using UV laser photocuring at 308 nm will significantly improve the speed of rapid prototyping of biocompatible and biodegradable polymer scaffolds and enables its production in a few seconds, providing high lateral and horizontal resolution. This short timescale is indeed a tremendous asset that will enable a more efficient translation of technology to clinical applications. Preliminary cell tests proved that PPF : DEF scaffolds produced by excimer laser photocuring are biocompatible and, therefore, are promising candidates to be applied in tissue engineering and regenerative medicine.

Elastin-Coated Biodegradable Photopolymer Scaffolds for Tissue Engineering Applications

“…It is therefore expected that elastin-coated materials can play a relevant role in activating the correct response in the injured vessel. This biological function was already demonstrated in several studies [2, 15, 24]. In addition, it was reported that elastin promotes in vivo endothelial cells adhesion and proliferation [27], which are responsible for all those mechanisms that regulate the platelet and smooth muscular cells overgrowth [28].…”

“…A photoinitiator (BAPO) is added to the polymer resin to enable the photocrosslinking reaction upon the exposure of UV irradiation [ 23 – 25 ]. Changing the parameters used for photocuring, such as photoinitiator and/or monomer concentration, and laser wavelength, pulse repetition rate, and pulse fluence (energy density per unit area), it is possible to achieve different aspect ratios and Young modulus of the produced scaffolds [ 24 ]. Finally, by using different masks, it is possible to produce a large variety of structures with desired porosities and to fabricate scaffolds, which are the most suitable for targeted applications in tissue engineering.…”

Integrating three-dimensional printing and nanotechnology for musculoskeletal regeneration

“…The geometry and architecture of the cured resin can be readily controlled by a focused laser beam [44–49] or digital mask projected from computer aided design interfaces [50]. This technology remains one of the most powerful and versatile, exhibiting the highest fabrication accuracy.…”

Modification of Physico-Chemical Properties of Acryl-Coated Polypropylene Foils for Food Packaging by Reactive Particles from Oxygen Plasma

“…The photon energy for this transition is 9.52 eV. The penetration depth of such UV radiation in a polymer material is around a micrometer [ 28 ]. The energetic photons cause bond scission and thus modification of the polymer properties well below its surface.…”