With the growing use of nanotechnology, our body is increasingly exposed to nanoparticles (NPs) either accidentally or intentionally in the case of nanomedical applications. Therefore, studies dealing with the translocation and effects of NPs at various biological tissue barriers are of key importance for the safe design of NPs for industrial, commercial and medical applications. The most common approach to study NP translocation in vitro are two chamber transfer systems, where the key cell types of the tissue barrier can be grown to confluency on opposite sides of a microporous membrane. However, the currently available membranes are only suitable for transfer studies of small molecules and drugs, but constitute a major barrier for the free transfer of larger molecules and NPs due to their high thickness, low porosity and artificial surface topography.

The aim of this master thesis project is to develop atomically thin microporous graphene membranes for predictive assessment of nanoparticle transport at biological barriers.

• Fabrication of supportive grids by laser ablation technique and optimization of graphene growth and transfer on the grids
• Exploiting polymer- and transfer-free direct-etching methods to produce suspended graphene membranes using photolithography approaches
• Graphene membrane perforation by focused ion beam (FIB)
• Membrane characterization (e.g. membrane integrity, thickness, porosity and pore size; permeability to molecules and nanoparticles)
• Development of tight cell layers/tissue barriers on porous graphene membranes and investigation of translocation of different compounds and nanoparticles
• Compare translocation rates to those from other in vitro models using commercial track-etched membranes and to ex vivo data

Interested candidates with a background in biomedical engineering, materials science, health science and technology or related fields may send a CV and short motivational statement including research in-terests as PDF or letter to:

Lea Furer, Empa-Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, CH - 9014 St. Gallen, Switzerland
Tel +41 58 765 74 91;
https://www.empa.ch/web/s403/particlesbarrier