Determination of glucose diffusion coefficients in biofilms with micro-electrodes.
A glucose micro-electrode was developed for direct measurements inside biofilms, and applied for the determination of effective diffusion coefficients in a model system of agar beads containing immobilized yeast cells. Two methods were used, one based on concentration gradients present at the liquid/solid interface of an active biofilm under steady-state conditions, the other based on the rate of glucose redistribution in an inactivated biofilm under transient-state conditions. Additional measurements with pH and oxygen micro-electrodes were performed and thus allowed for in-situ correction of the glucose electrode signal. From the micro-electrode measurements in the model system it was concluded that the glucose micro-sensor is a useful tool with which to obtain effective diffusion coefficients in biofilms.
Cronenberg
C C
CC
University of Amsterdam, Department of Chemical Engineering & Biotechnological Centre, The Netherlands.
van den Heuvel
J C
JC
D000362:Agar; D015374:Biosensing Techniques; D001709:Biotechnology; D004058:Diffusion; D005947:Glucose / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D010100:Oxygen; D012441:Saccharomyces cerevisiae
D000362:Agar; D005947:Glucose; D010100:Oxygen