Functional nanomaterials will play an increasingly important role in the future for solving current problems in medicine, biotechnology and environmental management - including the control of new and multi-resistant germs, personalized medicine and the development of sustainable biotechnological processes. They promise sensitive diagnostics at the single cell level or for small molecule ensembles, and down to the single molecule level if necessary. This requires materials that combine selective detection with a generally applicable transduction principle and a high transduction rate. Optical sensing based on nanoscale transducers (LSPR sensing - localized surface plasmon resonance) shows a high potential for broad application in bioanalytics with clear advantages (technically simpler detection, miniaturization, parallelization) compared to the established SPR (propagating surface plasmon resonance). To exploit this potential, novel and more sensitive plasmonic nanoparticles will be developed in the planned project. These are to be characterized by the combination of two sensitivity-enhancing effects: Shape anisotropy (silver prisms) and bimetallic particle structure. In anisotropic particles, an enhancement of the electromagnetic field is observed in certain regions of the particle (corners, etc.),
whereby a higher sensitivity for refractive index changes by analytes binding there is expected. This effect will be combined for the first time with the observed sensitivity enhancement by thin secondary metal layers on plasmonic nanostructures [1].
In order to bioanalytically exploit the advantages of such particles, a narrow size distribution (and thus the resulting spectroscopic properties) is necessary, which will be realized by the development and use of a microfluidic synthesis of these particles. 

The project is funded by DFG joint proposals under the number FR 1348/31-1; AOBJ 637250.