Refine
Has Fulltext
- yes (3)
Document Type
- Postprint (3)
Language
- English (3) (remove)
Is part of the Bibliography
- no (3) (remove)
Keywords
- Biophotonik (1)
- Energietransfer (1)
- Fluoreszenz-Resonanz-Energie-Transfer (1)
- Förster Resonanz Energie Transfer (1)
- Immunoassay (1)
- Lanthanoide (1)
- Lumineszenz (1)
- Nanopartikel (1)
- Optode (1)
- Quantenpunkt (1)
Institute
- Institut für Chemie (3)
- Extern (1)
Two examples of our biophotonic research utilizing nanoparticles are presented, namely laser-based fluoroimmuno analysis and in-vivo optical oxygen monitoring. Results of the work include significantly enhanced sensitivity of a homogeneous fluorescence immunoassay and markedly improved spatial resolution of oxygen gradients in root nodules of a legume species.
The salivary glands of the blowfly were injected with luminescent oxygen-sensitive microbeads. The changes in oxygen content within individual gland tubules during hormone-induced secretory activity were quantified. The measurements are based on an upgraded phase-modulation technique, where the phase shift of the sensor phosphorescence is determined independently from concentration and background signals. We show that the combination of a lock-in amplifier with a fluorescence microscope results in a convenient setup to measure oxygen concentrations within living animal tissues at the cellular level.
A technique has been developed to measure absolute intracellular oxygen concentrations in green plants. Oxygen-sensitive phosphorescent microbeads were injected into the cells and an optical multifrequency phase-modulation technique was used to discriminate the sensor signal from the strong autofluorescence of the plant tissue. The method was established using photosynthesis-competent cells of the giant algae Chara corallina L., and was validated by application to various cell types of other plant species.