This paper describes the development of methods for the determination of the characteristics and the behavior of living
neural cells. A technology which is used is the deep ultraviolet (DUV) modification of methylmethacrylate polymers
which leads to a new surface chemistry affecting the selective absorption of proteins and the adhesion of living cells in
vitro. The bi-functionality of the modified polymer chips supporting waveguides and cell anchorage capabilities at the
same time provides the opportunity to monitor protein adsorption, cell attachment and spreading processes by
evanescent-field techniques. This allows the defined spatial control of a cell/surface interaction and leads to a
combination of desired biological and optical properties of the polymer. Among them are the high sensitivity of cultured
mammalian cells to, for example, environmental changes and special features of integrated optical waveguides like their
online compatibility, minuteness and robustness. The scientific fields, biology and optics, meet at the polymer surface
becoming a cell culture substrate together with an optical waveguide by the application of special patterning and
fabrication technologies. In addition to the already mentioned fabrication and immobilization technology, the technique
proposed also offers the possibility of being able to couple to microstamping processes and to also incorporate electrical
measurements on individual cells. Thus, by extending this method and coupling it to the DUV technique described above
the possibility is given of being able to simultaneously optically and electrically interrogate individual cellular processes
with spatial resolution.
Deep UV-induced modification of the refractive index of polymers is a useful technique for low cost realization of
integrated optical circuits for telecommunication und sensor applications. The combination with replication techniques
like injection molding and hot embossing give the capability of a monolithic integration of these waveguide structures in
optical or fluidic microsystems. In addition the hybrid integration of these integrated optofluidic microsystems with
organic or inorganic photodiodes will open up the possibility to development novel, cheap, disposable integrated optical
sensors for environmental, chemical and biological monitoring.
We investigate the deep-UV-induced refractive index modification of alicyclic methacrylate copolymers for realizing integrated optical circuits for the development of cheap, disposable integrated optical sensors for chemical and biological monitoring. These novel copolymers obtain higher glass transition temperature (Tg), refractive index and lower water absorption than conventional poly(methylmethacrylate) (PMMA). At the same time, the adhesion of living mammalian cells on the UV exposed polymer surface was investigated for the application for biosensor.
Polymer optical waveguide devices will play a key role in several rapidly developing areas such as optical networks, biophotonic and fluidic applications. We have developed a technology which enables the increase of the refractive index of methylmethacrylate based polymers by deep ultra violet (DUV) radiation. The modification of the dielectric properties of polymers by DUV is a useful technique for the realization of photonic integrated optical circuits. The
technique presented here has several advantages with respect to common methods because only a single polymer layer is used, which serves as the substrate and waveguide as well and no further etching or development step is required. This method can not only be applied to planar polymer substrates but also to preembossed substrates. This enables the fabrication of ridge waveguide based devices by hot embossing. Nickel stampers with feature heights of about 15-20 μm and aspect ratios usually between 2:1 and 3:1 can be utilized for replication without major effort. Nickel stampers are not only used to replicate optical waveguides, but are also used to realize fluidic channels in the range of several microns. UV modification of methylmethacrylate polymers additionally leads to a new surface chemistry affecting the selective absorption of proteins and the adhesion of living cells in vitro. The bi-functionality of the modified polymer chips supporting waveguides and cell anchorage capabilities at the same time provides the opportunity to monitor protein adsorption, cell attachment and spreading processes by evanescent-field techniques.