Miniaturized biosensor for transducer molecule detection

Supervisor: C. Kranz

Lung epithelial cells are permanently exposed to chemical and mechanical stimulation. Physical forces may be sensed by these cells, and are then converted into biochemical reactions inducing intracellular signaling via specific signaling molecules. Hence, the selective and sensitive detection and quantification of such signaling molecules with temporal and spatial resolution plays a pivotal role. However, analytical approaches for detecting signaling molecules are frequently performed in a sequential manner with limited temporal resolution. Frequently, such signaling molecules are small molecules such as nitrogen monoxide or reactive oxygen species of limited lifetime, thus rendering their quantitative detection via conventional analytical techniques difficult. Miniaturized biosensors - in particular biosensors using electrochemical transduction principles - have gained significance in bioanalytical chemistry for detecting small signaling molecules. In particular, improved signal-to-noise ratios, fast response times, and the possibility to position them close to the surface of cell layers via scanning probe microscopy techniques renders them highly attractive for spatially and temporally resolved measurements of such signaling molecules. Recently, combined scanning probe techniques such as atomic force - scanning electrochemical microscopy (AFM-SECM) or the combination of scanning ion conductance microscopy (SICM) with SECM are particularly attractive, as the probes may be modified with biosensing architectures enabling the selective detection of signaling molecules.

Aim of the project is the development of novel miniaturized biosensors, which can be used in combination with scanning probe techniques for high-resolution detection of signaling molecules at lung epithelial cells