KROMKA Alexander Institute of Physics of the ASCR, v.v.i.

Fabrication of 3D Diamond Membranes for Microfluidic Systems

Co-authors VARGA Marian, BABCHENKO Oleg, BAUEROVA Pavla, HRUSKA Karel, JURKA Vlastimil, REZEK Bohuslav

A development of in-vitro systems addresses a number of technological issues (factors) which includes improved cell growth supports, exchange of cell growth medium, and embedded monitoring of cell culture conditions. For instance, use of three-dimensional (3D) support is becoming increasingly popular because closer biomimicking a native cell environment. Consequently, cells cultured on such supports behave more naturally comparing to traditional flat surface of Petri dishes [1]. Nowadays, artificial extracellular matrix (ECM) substitutes are commercially available since twenty years (e.g. Matrigel), introducing electrospinned artificial ECMs (e.g. UltraWeb) provided more reproducible results. Next, perfusion of cell medium through the cell culture, especially in microfluidic devices [2], further improve the natural in-vivo like conditions and represents highly attractive research field. The most recent demand is also for implementing opto-electronically active artificial ECM systems. With this respect, diamond thin films exhibit advantageous combination of physical, mechanical, chemical and electronic properties that make it highly biocompatible and multifunctional cell growth support [3, 4]. In this work we shed light on a technological fabrication of self-standing 3D diamond membrane for its implementation in microfluidic in-vivo like experiments. We applied two different fabrication strategies: i) the diamond CVD growth on porous 3D carbon foam (with 80 pores per inch) and ii) the selective area diamond growth predefined by photolithographic processing of seeding layer. The morphology and chemical composition of fabricated structures are characterized by scanning electron microscopy and Raman spectroscopy. We will compare and discuss the influence of selected technological factors on the formation of diamond-based membranes, i.e. type of surface pre-treatment (plasma vs. wet chemistry), seeding procedure (water vs. methanol based diamond powder suspension), and diamond growth regimes (focused vs. linear antenna MW plasma CVD system). Some of these factors will be shown as crucial for a successful implementation of the diamond membrane as smart and functional artificial support. ACKNOWLEDGEMENTS: This work was supported by P108/12/0996. LITERATURE: [1] A. Abbott, Nature 424 (2003) 870 [2] G.M. Whitesides, Nature 442 (2006) 368 [3] B. Rezek et al., Sensors 9 (2009) 3549 [4] M. Kalbacova et al., Acta Biomater. 5 (2009) 3076