No 5, Vol. 10, 2005, pages 434-436


J.J. Langer and K. Langer


Specific changes in the electrical conductivity of a polyaniline micro- and nanofibril network in the presence of microorganisms have been observed. The electrical conductivity of polyaniline (PANI) micro- and nanofibrils is strongly dependent on the temperature and the chemical environment. Both are locally modified by living cells, and this makes it possible to use polyaniline micro- and nanofibril networks as highly sensitive single cell biodetectors. The electrical response depends on the number of cells deposited on the PANI nanonetwork (e.g. from far below 100 to 2000) and is specific for different kind of microorganisms. The sensor is designed to apply in search for extraterrestrial life, but it also can be used to detect any kind of bio-contamination on the Earth.

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