New cellular sensing tool aids cystic fibrosis research
31 March 2006
Atlanta, USA. A new microelectrode that combines an atomic force
microscope with a biosensing layer has been used to investigate the cellular
energy transport chemical adenosine triphosphate (ATP) and its role in
The ATP study is the first application of the novel sensing system
developed by a research team led by Christine Kranz a senior research
scientist at Georgia Institute of Technology.
|Postdoctoral fellow Jean-Francois Masson
holds a microelectrode modified with a biosensing layer capable
of measuring adenosine triphosphate (ATP) release on cell
This patented technology adds recessed micro- and nano-electrodes to the
tip of an atomic force microscope (AFM), creating a single tool that can
simultaneously monitor topography along with electrochemical activity at the
The findings were presented at the American Chemical Society’s 231st
National Meeting in Atlanta on 26 March during a session on new approaches
in analytical chemistry.
The new multi-functional imaging technique will advance the study of
biological samples, said Boris Mizaikoff, an Associate Professor at Georgia
Tech’s School of Chemistry and Biochemistry and Director of its Applied
“Conventional AFM can image surfaces, but usually provides limited
chemical information,” he explained. “And though scanning electrochemical
microscopy (SECM), another probing technique, provides laterally resolved
electrochemical data, it has limited spatial resolution. By combining AFM
and SECM functionality into a single scanning probe, our tool provides
researchers with a more holistic view of activities at the cell surface.”
In addition to Mizaikoff and Kranz, the team also includes post-doctoral
scholar Jean-Francois Masson and graduate student Justyna Wiedemair.
In the ATP study, which is sponsored by the National Institutes of Health
and done in collaboration with Douglas Eaton at Emory University’s School of
Physiology, the Georgia Tech team used the multi-scanning biosensors to
study ATP release at the surface of live epithelial cells (cells that cover
most glands and organs in the body). ATP, a chemical involved in energy
transport, is of interest to medical researchers because elevated levels
have been linked with cystic fibrosis, a disease that affects one out of
every 2,500 people in the United States.
Using epithelial cell cultures from Emory, the Georgia Tech researchers
have demonstrated that their multi-functional biosensors work at the
live-cell surface during in vitro studies.
“Before you can identify what triggers the ATP release, we must be able
to quantitatively measure the released species at the cell surface,”
Mizaikoff said, noting that many pathological events involve the disruption
of chemical communication and molecular signalling between cells, especially
in the nervous system, lungs and kidneys.
Improved understanding of cellular communication can lead to new
strategies for treating diseases, Mizaikoff added: “Being able to operate
sensors in an electrochemical imaging mode at the micro- and nanoscale is an
exciting opportunity for complementing optical imaging techniques. There are
many clinical research problems that these biosensors can help with.”