Regensburg 2013 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 9: Posters: Membranes

BP 9.9: Poster

Montag, 11. März 2013, 17:30–19:30, Poster B2

Laser-spectroscopic Characterization of the Interaction between fluorescent Molecules and nano-sized Lipid Vesicles — •Alice Wilking, Idir Yahiatène, and Thomas Huser — Universität Bielefeld, Abteilung für Experimentalphysik, 33605 Bielefeld, Germany

Nanolipoproteins (NLPs) play an important role in the transport of bioactive compounds (e.g. cholesterol) through the blood. This work addresses the synthesis of NLPs and the investigation of their diffusion characteristics by Fluorescence Correlation Spectroscopy (FCS) to determine their size and shape in solution. We show the fabrication of 100 nm lipid vesicles using a mini-extruder. To make them visible the lipid vesicles were labeled with the lipid-intercalating fluorophore Di-I.

Di-I changes its photophysical character with its chemical environment. We also characterized Di-I by FCS, absorption and emission spectra in different solvents (changes in central wavelengths, dimer formation) and used dSTORM (direct Stochastical Optical Reconstruction Microscopy) to directly image and quantify the photophysical character of the dye; in its free and intercalated state. We found that Di-I is more photostable while it is intercalated. We also synthesized NLPs by mixing lipid vesicles with the protein ApoA-1. These NLPs are synthetic lipoproteins and as already demonstrated they portray a mean diameter of 7 nm - 15 nm. We have been able to confirm these values by FCS measurements.