MASTER THESIS Biomimetic potential of sponge ... - IAP/TU Wien

of rare earths (Zajec, 2010) or any mineral resource (Rekacewicz, 2009), these considerations
go far beyond material sciences. Apart from these implications, this approach might also
help to make our technology “greener”. Reducing our dependence on specific materials and
focussing on structures instead opens up possibilities for better MEMS and better control of
tribological properties (Gebeshuber & Gordon, 2011). These advances in nanotribology
would be an important contribution to a greener technology, helping us to address energyrelated
global challenges (Gebeshuber, 2012a) (Gebeshuber, 2012b).
In this chapter, however, the focus will be on materials that are inspired by the sponge
spicules in a more direct way, i.e. where the observed principles have been abstracted to a
lesser extent prior to their implementation. These applications obviously rely nonetheless on
the aforementioned general principles. Additionally the light transmitting and waveguide
properties of sponge spicules are very important.
Concepts learned from spicules
Research on sponge spicules has recently been driven by expectancies for useful
applications in nanotechnology. A major contributor to the knowledge about spicules and
especially spiculogenesis is the German-Chinese Joint Lab Nano-Bio-Materials and the
researchers at the affiliated institutions (National Research Center for Geoanalysis, Chinese
Academy of Geological Sciences, Beijing, Tsinghua University Beijing, Johannes Gutenberg-
Universität Mainz and others). They primarily focus on the development of intelligent
nanomedical biomaterials, e.g. for bone replacement to help patients suffering from
fractures or osteoporosis (Uni Mainz, 2011). In fact, nanotechnological materials for bone
replacement have been proposed by the researchers (Schröder et al., 2005) (Schröder et al.,
2007) (Müller et al., 2009c).
Another line of research has been pursued in Russia, where researchers took particular
interest in the optical, fluorescent and photonic properties of sponge spicules (Kulchin,
2011) (Kulchin et al., 2009) (Kulchin et al., 2008). They conclude that the non-linear optical
properties that arise because of the composite structure of silica and protein in spicules hold
great potential for applications in photonics. Non-linear optical behaviour can be detected
by using very short (~10 nanoseconds) laser pulses and observing the fluorescent response
at different light pulse intensities. The strong nonlinearity in sponge spicules has specifically
been attributed to the high concentration of irregularly interspersed organic compounds in
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