BioMEMS

Cells are usually studied in bulk quantities: they are suspended in a cell culture mixture and this suspension is usually analyzed. However, uncertainties and difficulties arise from the study of mixtures and volume fractions: for example it is extremely difficult if not impossible to discover a single cancerous cell in a population of healthy cells. It is immediately obvious that the study of individually-addressed cells can enhance our understanding of their structure and behavior. Here we present a device that allows the trapping, manipulation and simultaneous electrical/optical...

In a biological cell, enzyme systems play an important role since they direct the metabolism of the cell by controlling all processes to occur at a specific rate. One of the important research fields in cell biology is to investigate the structure and function of complex enzyme systems. However, the dynamic activities of enzymes in a living cell are hard to record. In this project, we probe NADH-Cytochrome b5 Reductase enzyme activity in a living cell by quantized plasmon quenching dips nanospectroscopy, a technology we developed earlier to detect the type of molecules conjugated on...

The project aims to develop an integration method for CMOS chip and microfluidics, specifically for immunosensing system with microfluidic system for sample preparation and CMOS magnetic sensor for detection. Solving the size mismatch between CMOS chip (typically mm scale) and microfluidics (cm scale) while maintaining the functionality and interconnect metallization of CMOS, as well as seamlessly delivery the fluid to the sensor surface on the CMOS chip through microfluidics are the key considerations for the integration. On the other hand, the integrated biosensor will be a...

We develop a technique for producing synthetic microbial patterns by means of direct activation and inactivation of gene expression in an initially homogenous population of cells using a microfluidic chemical interface system. A strain of E. coli was engineered such that the presence of the membrane diffusible molecule acyl-homoserine lactone (AHL) activates the production of more AHL, thereby creating a positive feedback loop. Since the half-life of AHL decreases in high pH solutions, this feedback loop can be inhibited in a specific area by modulating the local pH using a...