Research-Page of Dominik G. Rabus

Research

Bio-Photonics

The development of methods for the determination of the characteristics and the behavior of living cells including neural cells is the aim of this research. 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.

Patterned neural cells are shown in the photographs below.

The left photograph shows primary rat brain neural cells grown on 50 µm per side squares with 50 µm separating adjacent squares. The right photograph shows neural cells grown on 5 µm lines with 25 µm islands every 100 µm.

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.

The photographs below show cells and neural cells patterned on polymer waveguides.

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.