4.4 - Optical Biosensor Based on the Dependent Expression of Fluorescent Proteins
- Event
- SENSOR+TEST Conferences 2011
2011-06-07 - 2011-06-09
Nürnberg - Band
- Proceedings OPTO 2011
- Chapter
- O4 - Applications
- Author(s)
- J. Kothe, A. Schröter, G. Gerlach, K. Zarschler, G. Rödel, D. Wersing, M. Mkandawire, W. Pompe - Technische Universität Dresden (Germany)
- Pages
- 100 - 105
- DOI
- 10.5162/opto11/o4.4
- ISBN
- 978-3-9810993-9-3
- Price
- free
Abstract
There are still many measurement tasks in process engineering that cannot be solved by chemical or physical methods. The ongoing development of biological transducers provides many highly selective and sensitive assay solutions, which are only used in laboratory measurement systems up to now. It is our aim to investigate the potentials of a compact and robust optical biosensor that may be used for online measurement systems.
For a proof of principles we are building up a wholecell sensor that is based on yeast cells in a cellular amplifier system expressing a fluorescent protein depending on the concentration of heavy metals in solutions. Sensor cells react on the presence of a configurable stimulus with the production of a small soluble peptide, the yeast pheromone (α-factor).
These secreted molecules are disseminated to cells that thereby start expressing a fluorescent protein. A compact detection system for this fluorescence integrates excitation source, micro fluidic system, immobilized biological transducer and optical detector in a standard package to receive compactness and robustness. In the chosen transmissive topology the spectral signals of absorption and emission have to be separated by optical filters, where only one shall be used to reduce the complexity of the system.
We will present the results achieved with a test set-up that uses a pin diode detector and a LED excitation source. A model of the radiation in the measurement system allows the spectral simulation on the dependencies of excitation, absorption and emission of the fluorophore as well as an optimized filter design.
The fluorescence of biological thin layers was successfully detected. The performance of the measurement system was investigated by modeling and further experiments. Conclusions were used in the design of adapted interference filters for the selective detection of various fluorophores.