U. Beyer et R. Ehwald, Compensation of temperature and concanavalin A concentration effects for glucose determination by the viscometric affinity assay, BIOTECH PR, 16(6), 2000, pp. 1119-1123
A viscometer suitable for rapid measurements in small volumes of highly vis
cous liquids is described. Using this device the viscometric affinity assay
for glucose was studied under variable conditions in order to obtain basic
information for the design of a viscometric glucose sensor. The viscosity
of the dextran/Concanavalin A (ConA) solution is sensitive to glucose in a
broad range of the shear stress. However, for measuring the glucose concent
ration with this sensitive liquid the strong dependence of the absolute vis
cosity on temperature and ConA concentration has to be taken into account.
For the purpose of calibration a parameter more suitable than the absolute
viscosity is the relative fluidity (F-r) that is defined by the actual meas
ured viscosity at a given glucose concentration, the reference viscosity at
a standard glucose concentration, and a constant linearization coefficient
. F-r shows a linear dependence on the glucose concentration in the therape
utically interesting range up to 30 mM and is not significantly changed by
moderate variations of the ConA concentration or temperature.