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Lipophilic oligonucleotides, oligonucleotide-functionalized lipid vesicles and LbL-particles as tools for biotechnology. |
Collaboration with Institute for chemistry, Humboldt-University, Berlin, Structural biology of membrane proteins, Martin-Luther-University, Halle, Capsulution Nanoscience AG, Berlin, and Qiagen GmbH, Hilden sponsored by BMBF.
Oligonucleotides show a highly specific binding to complementary strands. A linkage of oligonucleotides to the surface of nano scale containers like vesicles or Layer by Layer (LbL)-particles gives, therefore, a unique tool for a targeted drug delivery and diagnostics. A combination of different approaches such as LbL-coating, synthesis of modified oligonucleotides, covalent coupling, LbL-particles with a magnetic or a soluble core, Förster Resonance Energy Transfer (FRET), Fluorescence Lifetime Imaging Microscopy (FLIM) is used in the project. Two strategies for a drug delivery by oligonucleotide-functionalized LbL-particles will be investigated: uptake into cells mediated, first, by complementary strands and, second, by a ligand-receptor binding. Magnetic LbL-particles are under development for diagnostics.
Results
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Lipophilic oligonucleotides incorporate into lipid membrane. |
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Sequence-specific binding of 3’Rh-A20mer oligonucelotides to T23mer-modified with two tocopherol anchors incorporated into N-NBD-PE-labelled (0.5 mol%) POPC-GUVs at about 1 mol% was followed by fluorescence microscopy (green - N-NBD-PE; red - 3’Rh-A20mer). |
| Oligonucleotides can be covalently coupled to the LbL-particles. These LbL-particle show sequence-specific binding of the complementary oligonucleotides. | |
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FITC-A21 is covalently bound to the surface (left). Red fluorescence on particle surface is observed after adding Rhodamine-T20 (right). FRET can be observed using confocal microscopy |
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