Nanoplasmonic biosensors and chemosensors

In-line-capable bio- and chemosensors are steadily gaining importance in the constantly growing fields of application in medicine, biotechnology, food technology and environmental analysis. For continuous process monitoring, concentrations of (bio)chemical measurands must be determined quickly and directly on site, which cannot be accomplished with current analytical laboratory methods.

Specifically functionalized, fast and process-integrated

To address these needs, the research group is focusing on a nanoplasmonic sensor platform in miniature format. Therefore, the optical laboratory method of surface plasmon resonance (SPR) spectroscopy, which is used to specifically and rapidly detect molecules with high accuracy, was further developed into an on-site analytical method. The compact optical system consists of a sensor chip developed and manufactured at Fraunhofer IKTS on a foil, a LED light source and an optoelectronic readout unit. Since no further optical components are required, the system is compact, robust and cost-effective, thus allowing direct integration into industrial equipment.

By means of a specific chemical functionalization (with polymers and biomolecules), the surface of the sensor chip can be activated so that the presence of a specific, (bio)chemical molecule (=analyte) in a mixture of substances causes a concentration dependent change of the optical properties of the sensor.

Fields of application

In-line process monitoring of (fermentation) tanks
On-site analysis of anthropogenic trace contaminants (e.g. diclofenac) in water treatment in nanomolar (nM) to micromolar concentration ranges
Plasmonic measurement and monitoring of process parameters, such as ion concentrations and pH, via swelling of hydrogels

Services offered

Electrodynamic simulation of nanostructured gold surfaces/sensor surfaces
Fabrication of gold surfaces/sensor surfaces by nanoimprint lithography
Realization of microfluidic sensor chips
Development of adapted (bio)assays for on-site process monitoring and environmental monitoring
Targeted (bio)chemical functionalization of the measurement surfaces
Development and construction of process-integrated devices (together with industrial partners)
Comprehensive optical characterization of (bio)assays