Research
The Laboratory for Sensors deals with different sensory questions, mainly in the field of medicine and biological application. The spectrum is from basic research via applied research until technology transfer into industry.
Electrochemical sensors, biosensors
| One of the main competences of the laboratory is the development, fabrication and application of chemo- and biosensors. Different sensors for glucose, lactate, glutamate, oxygen, pH, NO as well as ion selective sensors are available. By using different enzymes on a single chip multiple parameters can be measured simultaneously. Investigation of electrode and membrane properties as well as the measurement of catalytic parameters can be done by Scanning Electrochemical Microscopy (SECM). |
Sensors for in vivo application
| We develop microsensors for in vivo application in living tissue. Therefore, flexible microprobes are applied on which various electrochemical sensors are integrated. It allows the continuous, highly sensitive online-monitoring of e.g. glutamate, lactate or oxygen levels in situ, directly in the tissue. These sensors can be applied e.g. in the brain. |  |
Cell culture monitoring, microphysiometry
| The Sensing Cell Culture Flask (SCCF) enables continuous, long-time monitoring of different chemical and biochemical parameter cell cultures. This is an important tool for standardisation of cell cultures as well as for specific research. The platform allows the integration of amperometric and potentiometric sensors, for example oxygen, pH, NO and biosensors. |
Lab-on-a-Chip, microfluidics
| With our lab-on-a-chip platform technology complex microfluidic structures can be developed due to its large design flexibility. Therewith, it is possible to generate very fast different modules for a total assay development. One focus is on the development of miniaturized and integrated lab-on-a-chip systems for biomedical analysis of different bio processes as well as detection of RNA oligonucleotides (small RNAs, ncRNA, µRNA and specific mRNAs). Established chip-based sample pretreatment modules (enrichment, lysis and purification) can be within short time (≤ 15min) directly applied in RNA and/or DNA analysis of bacteria, viruses as well as eukaryotic cells (human, mouse, rat) and green algae. |
Dry-film photoresist based electrochemical microfluidic biosensors for on-site applications
iLab is our unique biosensor platform which combines microfluidically actuated enzyme capillaries with an electrochemical detector cell. The flexible and disposable sensor chips are fabricated in a low-cost dry-film resist technology. The utilization of microcapillaries results in a high surface-to-volume ratio allowing significant shorter assay times. This platform offers various biosensors with a microfluidic channel or channel network of two, four or eight distinct immobilization sections, each with a volume of under 1 µl. By means of individual channel inlets they can be actuated seperately which enables a high assay flexibility regarding its format (e.g. competitive) and its technology (e.g. proteomics). Different bioassays can be implemented. Thus, sensors for testosterone, troponin I, substance P, CCL18 and various antibiotics (e.g. penicillins or tetracyclines) have been realized. |
Biocompatibility
A special PECVD polymerisation process allows the deposition of amorph, hydrocarbon-based films in the nanometer range. These nanofilms display antifouling-properties without harming their surrounding. The aim of these coatings is to impart substrates with biocompatibilty independent of their shape, size or material. |
Parylene coatings
| Through a cooperation with Prof. Yasuda, the Chair for Sensors developed a special Parylene deposition equipment, which combines a plasma process and a standard Parylene coating process. The effect of the plasma process on the adhesion and barrier properties of the Parylene layer are under investigation and continuously optimized. The main applications are in the field of biomedical technology but is not restricted to it. » more |
Gas sensors
| Gas sensor systems represent an exciting area of research which recently has been established at the chair. The research focuses on the development and the preparation of gas sensitive materials characterized by improved selectivity for target gases and increased gas sensitivity at moderate temperatures. These materials are developed, particularly with regard to innovative gas sensor applications based on the work function measurements. |
Nanosensors, nanomaterials
| Nanomaterials differ considerably in their properties from the bulk analogues. Only by size reduction to the nanoscale, optical, electrical and catalytic properties of materials can be strongly affected due to occurring of quantum mechanical effects and changes of structure or morphology. Nanomaterials are extremely sensitive to their environment. Both, their high reactivity and unique properties we utilize for applications in sensor systems. For this purpose metallic, bimetallic, metal oxide and semiconducting nanoparticles as well as metallic nanowires and metal-organic frameworks (MOFs) are prepared by various synthetic procedures. Metallic nanoparticles are used for the decoration of sensor materials such as carbon nanotubes (CNTs), metal oxide films or metal oxide nanowires (NWs), for example SnO2, WO3, CuO. | |
Carbon-based nanostructures
| The Chair for Sensors developed an experimental reactor to deposit carbon-based nanostructures on small substrates. Depending on the parameters, one can deposit carbon nanotubes (CNTs) or carbon nanowalls (CNWs). The main applications of the obtained structues are catalysis, energy storage und gas sensors. » more |
Thermal sensors
The Laboratory for Sensors has a great experience on temperature sensors that spans for over 15 years. Extremely sensitive amorphous germanium thermistors allow for a temperature resolution of 0.1 mK and long term stability (0.25K/year). The thermal conductivity of in vivo tissues can be measured with an implantable needle with an array of thermistors. The thermal conductivity can be used to monitor the development of foreign body reaction. In vitro, nano-calorimeters allow for the determination of the denaturation temperature of glucose oxidase and other proteins, and the monitoring of bacterial biofilm development. |
Flow sensor technology
| Based the germanium technology for thermistors highly sensitive thermal flow sensors have been developed. The use of thermally insulating membranes results in very low power consumption (< 1mW). Currently, research focuses on developing auto-calibration techniques to achieve medium independent flow measuring. For this, thermal properties of gases are measured under flow conditions. |
Fuel cells
| Based on our expertise in fabrication and functionalization of nanostructures we develop novel electrodes for application in fuel cells, especially in biofuel cells, and as an storage for charge. |