Funding tool: Basic research projects
Project-ID: LS13-022
Project start: 01. Februar 2015
Project end: will follow
Runtime: 24 months / finished
Funding amount: € 232.000,00

Brief summary:

The point-of-care and home-care market are fast expanding branches of medicine. In order to promote the concept of patient-near and personalized therapy, portable analytical devices are required as alternatives to the time-consuming diagnostics in standard laboratories. We work on the development of point-of-care methods for the biomolecular diagnostics which rely on a novel mechanism based on multifunctional magnetic nanoparticles. An in a magnetic field guided rotation of such hybrid nanoparticles responses on the attachment of biomolecules at their surface by a phase lag signal which is easily detected by optical means. The detection method is highly sensitive, simple to realize and compact. The performance of the concept could be demonstrated with representative biomolecules like streptavidin, BSA, and HER2, up to now. However, the sensitivity is severely limited by the material inhomogeneity and the size distribution spread of the available hybrid nanorods from a chemical synthesis. In addition, the momentary first experimental setup should be improved.

In this proposal, novel hybrid nanoparticles should be developed by physical methods which feature clear advantages compared to the chemical synthesis. Thin films will be structured by lithographic methods to asymmetric nanoparticles. The thin film technology bears the advantage that different intended properties can be tailored by nearly arbitrary material choice and combination. The reproduction process by nanoimprint lithography finally guarantees an inexpensive production and sufficient quantities. Both the magnetic properties and the plasmonic amplification can be optimized in such a system. Up to now, the latter could not be realized with the chemically synthesized nanoparticles despite many experimental trials because the noble metal coating of the magnetic core stays inhomogeneous due to thermodynamic reasons. However, recent simulations suggest a sensitivity increase of at least a factor 100 in the presence of plasmonic amplification. A further factor 10 is expected by the improvement of the momentary setup. Recent measurements on HER2, a marker relevant for metastatic breast cancer, show a limit of detection of 10 nM. By the improvements suggested in this proposal, sensitivities will be increased to the point which is necessary for routine clinical investigations, or even better. As test systems, we plan HER2 in blood and Interleukins for sepsis detection as an important point-of-care case.

Keywords:
molecular diagnostics, nanotechnology, magnetic particle, cancer detection