Direct Laser Fabrication of Biomimetic, 3D Scaffolds for Tissue Regeneration

Contact Person(s):​​ Dr. Emmanuel Stratakis, Α. Ranella, P. Kavatzikidou

Short Description and Main​​ Findings of the Research Topics:

Research Topic 1: Direct Laser Micro/Nano Fabrication of Biomimetic Scaffolds

Short description

The aim is to investigate the biocompatibility of laser-engineered biomimetic 3D scaffolds fabricated on hard metallic and soft polymeric materials, exhibiting different micro/nano topographies and surface energies.

Abstract

The​​ extracellular matrix provides the necessary cues at micro and nano-scale for cell adhesion, alignment, proliferation and differentiation. In this​​ context,​​ the surface topography of biomaterials can have an important impact on cellular adhesion, growth and proliferation. Apart from the overall roughness, the detailed morphological features, at all length scales, significantly affect the cell-biomaterial interactions in a plethora of applications including structural implants, tissue engineering scaffolds and biosensors. 

The main objective is to investigate the biocompatibility of laser-engineered biomimetic 3D scaffolds fabricated on hard metallic​​ and soft polymeric materials, exhibiting different micro/nano topographies and surface energies.​​ ​​ Ultrafast pulsed laser irradiation is considered as a simple, precise and effective microfabrication method to produce structures of controlled geometry and pattern regularity. The variation of irradiation parameters, such as fluence and irradiation environment gives rise to significant changes of the surface morphology attained (i.e. geometry, dimensions and density of the structures). As a consequence, morphologies ranging from microcones to nanoripples (Figure 1), as well as hierarchical micro/nano structures (Figure 2) can be fabricated and further used as cell culture platforms.​​ 

The laser fabricated scaffolds with controlled surface roughness, wettability​​ and surface energy can be used as model platforms to study the influence of topography on cell response. It is demonstrated that, depending on the laser processing conditions, distinct cell-philic or cell-repellant patterned areas can be attained with a desired motif (Figure 3). Laser processing could thus enable spatial patterning of cells in a controllable manner, giving rise to advanced capabilities in cell biology research.

Research has shown that cell adhesion and migration could be tuned via the laser-patterned substrates. It was also shown that microconical substrates could influence sympathetic and sensory neuronal alignment as well as NGF-induced PC12 cell differentiation (see also Research Topic 2).​​ 

Scaffolds on hard materials

Figure 1:​​ Various types of femtosecond laser fabricated scaffolds on hard materials with feature sizes ranging from a few hundreds of nanometers to tens of microns​​ (C Simitzi, P Efstathopoulos, A Kourgiantaki, A Ranella, I Charalampopoulos, C Fotakis, I Athanassakis, E​​ Stratakis, A Gravanis, Biomaterials, 2015, 67: 115-128, doi.org/10.1016/j.biomaterials.2015.07.008).