10-56
examined later). For detection of sugars, the pulse sequence is as follows: the first
pulse cleans the electrode surface and deposits an oxide layer on the surface, the
second pulse reactivates the electrode surface by removing the oxide layer and
adsorption of the analyte occurs, and detection occurs on the third pulse. During an
analysis, the potential pulses are constant. However, the TPTB mode has the
capability of scanning the potentials by increments, which is useful during method
development for determining the optimal potentials for the analysis. Although this
specific example has been given, TPTB should be considered as a general purpose
wave form that could be used for many electrochemical sensor applications.
E
SAMPLE
WIDTH
DATA 3
INIT. E
SAMPLE WIDTH
DATA 2
1 CYCLE
SAMPLE WIDTH
DATA 1
INCREMENT DATA 1
INCREMENT DATA 3
INCREMENT
DATA 2
t
QUIET
TIME
Figure 10-38. Potential wave form for TPTB.
Figure 10-39. Current response for TPTB (Data Set 3).
Mode = TB
General Parameters
Initial E (mV) = 0
-3276 to 3276
Sample Interval (msec) = 500
50 to 20000
Run Time (sec) = 4000
1 to 65535
