Beckman Coulter AU2700, Руководство пользователя

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Automated Chemistry Analyzer
AU2700 User's Guide
Chapter D - Software
D-127
May, 2002
The slope check and update measurement in calibration are performed as described below.
Slope check
Measure each standard solution once, and then check if the two kinds of measured values
of H-STD and L-STD are both within the limit values based on the previous calibration
values. If both are within the limit values, the measured values are judged as unfluctuating
in comparison with the previous ones.
If measured values are judged as unfluctuating, four-time measurements for each standard
solution necessary for calibration update after slope check can be omitted. If this is the case,
the previous slope value and MID solution correction factor are output as the calibration
results.
Calibration update measurement
If measured values are judged as fluctuating in comparison with the previous ones as the
result of the above slope check, each standard solution is measured four times, and the
calibration is updated.
Correction by M-CAL:
M-CAL for the ISE corrects results using this formula, Y = AX + B.
Coefficients A and B are obtained in the following way. Perform a regression analysis
between measurement values from this system without an M-CAL data correction and a
conventional or basic method: Y=aX+b
Where Y = measurements from this system, and
X = reference values using the conventional method or basic method.
X=(1/a) Y-(b / a). Thus, A=1/a,B=-b/a.
Correction by A-CAL:
c'
c
C
X (known concentration of a specimen subject to A-CAL)
Y (measured value) ● Corrected value: c' - c
● b'=b-(c'-c)
a = factor
b = offset
OLP4083
b'
b
Y=aX+b
Y=aX+b'
To use ACAL, assay a calibrator with known concentration, C. The result obtained for this
sample by A-CAL after an M-CAL correction will be C ’ . In order to correct the concentration of
samples run for A-CAL, the instrument calculates the difference between C and C ’ . This A-CAL
correction is applied to values in addition to any M-CAL correction coefficients B.