Laser sintering fabrication of three-dimensional tissue engineering scaffolds with a flow channel network

Abstract

The fabrication of tissue engineering scaffolds for the reconstruction of highly oxygen-dependent inner organs is discussed. An additive manufacturing technology known as selective laser sintering was employed to fabricate a highly porous scaffold with an embedded flow channel network. A porogen leaching system was used to obtain high porosity. A prototype was developed using the biodegradable plastic polycaprolactone and sodium chloride as the porogen. A high porosity of 90% was successfully obtained. Micro x-ray CT observation was carried out to confirm that channels with a diameter of approximately 1 mm were generated without clogging. The amount of residual salt was 930 µg while the overall volume of the scaffold was 13 cm(3), and it was confirmed that the toxicity of the salt was negligible. The hydrophilization of the scaffold to improve cell adhesion on the scaffold is also discussed. Oxygen plasma ashing and hydrolysis with sodium hydroxide, typically employed to improve the hydrophilicity of plastic surfaces, were tested. The improvement of hydrophilicity was confirmed by an increase in water retention by the porous scaffold from 180% to 500%.

Combined additive manufacturing approaches in tissue engineering

“…In particular, several studies have reported the implementation of AM techniques (such as 3D printing [92]) with different porogen leaching systems, and, more recently, the use of SLS to create highly porous structures with embedded flow channel networks [93]. However, most AM approaches are not compatible with local-pore fabrication processes (i.e.…”

Biomedical Optics and Lasers

“…These synergetic developmental changes expand application scope and speed of laser in bioindustry. Rapid fabrication (prototyping) of prosthesis or scaffold [104] with LS before the surgery has 2 major advantages for the surgeon and the patient. First thing first, operator has the ability to work on this study model before the surgery and is capable to prepare any kind of framework or a template, even in complex 3D architecture, to be used as a fixation or stabilization material etc.…”

Development of a novel micro-ablation system to realise micrometric and well-defined hydrogel structures for tissue engineering applications

“…The former includes membrane lamination (Mikos et al, 1993), 3D printing (Butscher et al, 2011), laser sintering (Niino et al, 2011), photo-polymerisation (Kawata et al, 2001) and 3D system multi-jet modelling (Klebe, 1988). Techniques such as fused deposition modelling (Zein et al, 2002), 3D bio-plotter (Fedorovich et al, 2008), bio-printing system (Mironov et al,, 2003) and pressure-activated microsyringe system (Vozzi et al, 2002; belong to the second group.…”