Microfabricated Biosensors

• Bio-Compatibility Laboratory
  
• Sensors and Instrumentation Group

Erno Lindner, PhD

The use of electrochemical cells for chemical measurements is well-established in analytical chemistry. The most striking and unique features of electrochemical microsensors are the extremely local, direct measurement of ion activities and/or various substrate concentrations, the depth-profile recordings in tissue, measurements of activity transients in the ms range and the simultaneous assessment of electrical parameters. In our group we adapt the existing semiconductor and microelectronics technologies to produce closely spaced sensor arrays on different substrates (e.g., flexible Kapton® or rigid ceramics). Our long term goal is to make the strategic step from acute toward chronic measurements, i.e. toward implantable sensors which are sterilizable, biocompatible, and do not need frequent calibration. To improve the performance characteristics of Ion Selective Electrodes and extend their response range a new analytical technique has been invented to study membrane processes during electrochemical control. It allows the direct visualization of the transport of chemical species within a sensor membrane during potentiometric and chronoamperometric measurements. The work is made in extensive collaborations with other universities.

We have begun collaborating with the Infectious Diseases program at St. Jude Children's Research Hospital, to develop a sensor to detect hydrogen peroxide produced by the respiratory pathogen, Streptococcus pneumoniae. In a collaboration with LeBonheur Children's Hospital our ion sensor technology is adapted for use at the bedside of patients in the intensive care unit.

Analytical Chemistry Laboratory:

• Scanning Electrochemical microscope
• Impedance spectroscopic measurement

Microfabrication Facility:

• Micro-fabrication facility
• Photolithography
• Thick- and thin-film micro-fabrication
• Soft lithography
• Device packaging
• Hybrid micro-electronics
  

• Ion-selective electrodes with sub-nanomolar detection
• Differential gas sensors for CO2
• Enzyme activity sensors
• Micro-electrode arrays for O2 and H2O2
• Compliant strain sensors
• Temperature sensors and arrays