Multi-channel solutions for optical labelfree detection schemes based on the interferometric and grating coupler principle

In this work novel concepts for the realization of multi-channel optical labelfree sensors are presented. The concepts aim at two important fields of application, namely the high throughput screening and the so called high content screening with two different optical labelfree sensor approaches. Cheap disposable sensor units are of importance for HTS. Here embossed gratings which may act as transducers or coupling elements in the sensor units are characterized and investigated. The gratings have been embossed in glass, Sol-Gel or Ormocer. Different concepts where embossed gratings may be implemented for HTS are presented and their feasibility investigated. A promising approach for applications where binding kinetics is monitored is the interferometric sensor principle. The Young-Interferometer which consists of an integrated optical Y-branch with a differential sensor principle is investigated and characterized regarding the noise resolution. As application examples, experimental results on the detection on small molecules, the streptavidin-biotin interaction are given. Results from measurements where the Grating Coupler and the Young-interferometer are compared regarding the suppression of the response to nonspecific binding are presented. The present noise resolution of the Young-interferometer was determined to Delta-N=3*10-8 which corresponds to a surface mass coverage of Delta-G =650 fg/mm². Furthermore, multi-channel concepts based on the present Young-interferometer are considered. Here a novel interferometric sensor, the so called MMI-sensor, with a multimode interference section as wave splitting device and with non-equidistant branches is presented. The novel sensor has in addition to multichannel potential also the possibility to correlate the sensor response to the corresponding sensor branch. This is a feature that opens up the possibility of further drift compensation and also suppression of the response from nonspecific binding on the sensor surface.

Author dc:creator

• Wikerstål, Andreas

Contributors dc:contributor

• Urban, Gerald A.

• Young-Interferometer
• integrated optics
• grating coupler
• optical waveguides
• labelfree

Repository record source_url

https://freidok.uni-freiburg.de/data/317

OAI identifier oai:identifier

oai:freidok.uni-freiburg.de:317