Single-Choice Kapitel 4

Blood glucose concentration for diabetic patients can reach levels of even up to 500 mg/dl.

Diabetic patients can suffer from both too low and too high blood glucose levels.

For H2O2 determination in glucose biosensors, the resulting current is inversely proportional to the glucose concentration.

Glucose biosensors of the 2nd generation enable a direct eletron transfer between the enzyme and the working electrode of the sensor chip.

The mediator in glucose biosensing will regenerate the enzyme into its oxidized form.

The mediator in glucose biosensing will regenerate the enzyme into its reduced form.

Coulometric and amperometric biosensors are both measuring a current as the sensor output signal.

For glucose biosensing (1st generation) H2O2 will be oxidized at -600 mV and O2 will be reduced at +600 mV.

For glucose biosensing (1st generation) H2O2 will be reduced at +600 mV and O2 will be oxidized at -600 mV.

For glucose biosensing (1st generation) H2O2 will be reduced at -600 mV and O2 will be oxidized at +600 mV.

For glucose biosensing (1st generation) H2O2 will be oxidized at +600 mV and O2 will be reduced at -600 mV.

For glucose biosensing (1st generation) a limited sensitivity is given due to the oxygen solubility in blood.

For glucose biosensing (1st generation) the influence of oxygen variation in blood can be compensated by a differential sensor set-up with an additional oxygen sensor.

Microcantilever sensors can be operated in static or dynamic deformation mode.

Microcantilever sensors utilize a change in the resonance frequency when read out in the static deformation mode.

Microcantilever sensors have a typical microcantilever dimensions of (L,W,H) of 100 μm, 20 μm, 1 μm.

Microcantilever sensors have a typical microcantilever dimensions of (L,W,H) of 500 μm, 1 μm, 0.5 μm.

Microcantilever sensors measure the deflection of the cantilever by optical or piezoelectric transducers.

Microcantilever sensors coat both sides of the cantilever with a receptor layer to increase sensitivity, especially when operated in the static deformation mode.

Mass-sensitive sensors utilize thickness shear vibration of surface acoustic wave propagation.

QCM is based on the inverse piezoelectric effect.

SAW sensors possess a higher overall sensitivity towards analyte molecules than QCM sensors.

For Sauerbrey equation, there is a square dependency between frequency change and the concentration of the analyte.

In QCM, depending on the measurement mode, one or both sides of the resonator can be in contact with the analyte.

For the detection of cells, surface imprinted polymers are preferred over molecularly imprinted polymers.