Microbial Biosensors

Project BioMicroFlow | Project Screening Sensor

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A biosensor is an analytical device that combines a biological sensing element with a transducer to produce a signal proportional to the analyte concentration. The transducer converts the biological signal into a measurable response, which can further amplified, processed and stored for later analysis.

The basis of a microbial sensor is the close contact between microorganisms and the transducer, thus, the fabrication requires immobilization on transducers with a close proximity.
In order to develop selective microbial biosensors the use of such microorganisms is important, which have a narrow substrate spectrum. The respiratory activity of the microorganisms was estimated by monitoring the oxygen consumption using an automatic flow system. The microorganisms are immobilized on a membrane. At present the GMBU e. V. work on the project BioMicroFlow to developing a miniaturized fluidic system.

The electrochemical bioactivity sensor (BAS) provides an other measuring system for determining the activity of microorganisms regarding potential substrates. This principle serves the characterisation of certain metabolic characteristics of a strain of microorganism or a mixture of heterogenous microorganisms.

For that purpose a defined sequence takes place, for instance with potential subtrates. The resulting signal pattern gives finally information over the metabolic potential of the target strain (screening of substrates or adaption on specific conditions). Likewise the effect of inhibitors or activators is relatively simple to examine with this screening sensor.
An automatic change of the microorganism sample in the measuring cell permits an online bioprocess monitoring, e. g. the biological step of an sewage treatment plant, in order to examine dynamic changes of the metabolic activity of process biology.