12 research outputs found
High intensity plasma immersion metal ion beam source for surface modification of materials
Lichtadressierbare potentiometrische Sensoren und deren Einsatz zur ortsaufgelösten Konzentrationsbestimmung.
Neue Ansteuerungselektronik für LAPS-basierte Biosensoren zur gleichzeitig ortsaufgelösten Messung der pH-Konzentration
Neue Ansteuerungselektronik für LAPS-basierte Biosensoren zur gleichzeitigen ortsaufgelösten Messung der pH-Konzentration
On-line determination of the condition of microorganisms by a light-addressable potentiometric sensor
Array-based light-addressable potentiometric sensor with integrated imaging correction mode
Determination of the extracellular acidification of Escherrichia Coli by a light-addressable potentiometric sensor
The monitoring and control of a biogas digester is important to maximise the energy output and to avoid down times. Within the digester process, the metabolic activity of relevant organisms represents a key parameter. A light-addressable potentiometric sensor (LAPS) can be used to determine the extracellular acidification of these organisms. With the developed on-chip differential LAPS set-up, external influences, like sensor drift, temperature fluctuations and external pH changes can be compensated. An immobilisation protocol based on polyacrylamide has been developed to immobilise the organisms on the sensor surface. To validate the system, Escherichia coli have been used as a model organism. Measurements with E. coli in suspension and measurements with E. coli embedded in polyacrylamide gel were performed. It was shown, that the activity of the E. coli in the polyacrylamide was as high as in suspension, when determining the effect of the immobilisation towards the extracellular acidification rate. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei