The Working Group Microsensors & Microfluidics concentrates on the miniaturization of sensoric and fluidic systems based on silicon, glass or polymers and offers corresponding technologies.

One of our activities focuses on the development of highly miniaturized active medical implants, some of them which can be placed in the oral cavity, such as the salivary stimulator Saliwell with closed loop control as well as the drug delivery system IntelliDrug.

In the field of microfluidics we focus on realizing microfluidic systems to handle biological cells, e. g. cell transportation or cell separation.

The Working Group also concentrates on the integration of biochips in Lab-on-Chip. We are well grounded in a long-standing know-how as well as numerous technologies for biochip-compatible assembly and interconnection technologies and the realization of microfluidic systems. Above all, the interdepartmental cooperation within the Working Groups Biosensors and Microarray & Biochip Technology allows a customized development of complete analysing systems.

Microfluidic channel systems combined with electrodes can either be made of polymeric materials or using classical MEMS materials like silicon and glass. Biocompatible dry film resists as well as SU-8 photoresist can be applied for prototyping and for small batches. Real mass production is possible by exploiting a new roll-to-roll hot embossing process in combination with capping of embossed micro channels by a rotative lamination process. Materials like COC, PC, PMMA, PS, etc. are available.

Examples:
- micro injection chip
- cell sorting chip
- micro- and nano patterned surfaces for studying cell behaviour

Silicon based MEMS technology in combination with additional micro system technology allows fabricating miniaturised sensors and actuators. An emphasis is on sensors and actuators for medical devices, especially medical implants. In the past a focus was on miniaturised systems for application inside the oral cavity.
On demand: all sensors and actuators can be provided with a telemetric link for wireless control or data transfer.

Examples:
- micro flow sensor for a drug delivery system
- wetness sensor for the oral cavity

Microfluidics and biochip-compatible packaging are the typical enabling technologies which can convert a bare biochip into a device practically usable in the macroworld. Microfluidic technology provides the interface for the fluid supply of miniaturized biosensor elements. Several concepts and technologies for supplying the fluids to the biosensor element as well as for the fluidic interface to the user are available. They take into account that sample injection should only contaminate the cheap and disposable parts of the system. Furthermore concepts and technologies for the electrical interface are available. The applied micro-assembly and encapsulation techniques ensure a strict separation between fluid channels and sensible electronic structures on biochips and lab-on-a-chip systems.

Examples:
- Packaging of a multianalyte biochip based on an array of nine monolithic optoelectronic transducers
- Packaging of a silicon-based resonating-type biochip