RADIOMETER ABL800 FLEX, Reference Manual

Page: 59 / 206

2. Amperometric measuring principles ABL800 FLEX Reference Manual
Metabolite electrodes,
Continued
Stability criteria
(continued)
τ
= Should be less than or equal to 50,
and
upd.21) 1, I(Cal upd.11) 1, I(Cal
upd.11) 1, I(Cal upd.1) 1, I(Cal
log
−
−
should be negative or equal zero.
The following stability criterion must be met to obtain a stable electrode response
during measurement:
S
d,zero
< S
d,max
where:
S
d,zero
= Spreading of the zero point current updatings around the
regression line.
S
d,max
= If Sens
>
400 pA/mM, then S
d,max
= 0.025
×
Sens,
otherwise S
d,max
= 10.0.
The (glucose or lactate) in the sample is c X(sample,corr).
If the corrected concentration of the metabolite, c X(sample,corr)
>
1, the following
criteria must be fulfilled:
20 0.
) ero ( I upd.30) I(sample,
I 9 upd.21) I(sample, upd.30) I(sample,
0
0
slope ≤
−
× − −
≤
z
otherwise
14 . 0
Sens
I 9 upd.21) I(sample, upd.30) I(sample,
slope ≤
× − −
where:
I(sample,upd.30)
I(sample,upd.21)
= Electrode current at the 30
th
/21
st
updating during
measurement on sample, respectively.
I
0
(zero) = zero current extrapolated to the time of the
measurement.
Continued on next page
2-20