Biomedical Engineering Reference
In-Depth Information
Sensitivity
LLOQ = S/N ³ 5
Accuracy: 80-120 %
MRL is confirmed by: Upper
PIR = (Mean + HR
PIR
)/forti fi ed
concentration × 100 £ 150 %
Lower PIR = (Mean − HR
PIR
)/
forti fi ed
concentration × 100 ³ 50 %
LOD = S/N = 3
LOQ = the lowest
measureable
concentration of
actual sample with
interassay CV < 20 %
Sample
stability
3× Freeze-thaw cycles for
samples between −70 °C
and room temperature;
4-24 h at room temperature;
long-term storage; sample
stock and postpreparation
stability.
5-10 ng/L × 6 at £ 6 °C for 28 days
NA
3× Freeze-thaw cycles
for samples between
−20 °C and room
temperature;
Ambient and 4 °C for
7 days
Internal
standard
Isotope labeled analyte with
optimized binding
assessment, and verified
standard curve
IS peak area within ±50 % of each
analyte
13
C
6
-Estradiol, 16 a -Hydroxyestra-
diol-
d
2
, Testosterone-
d
3
,
13
C
2
-Etheylnylestradiol
IS peak area within ± 50 % of each
analyte
Testosterone-
d
3
, Estradiol-
d
3
Estron-d
4
, Estradiol-d
5
QC samples
Replicates at three levels,
e.g., LQC (3× LOQ),
MQC and HQC
67 % (4 out of 6) within ± 15 %
of nominal value
Single run of LQC, MQC, …
and HQC
LQC within ± 50 % of nominal
value, and others within ± 30 %
Single run of working standards at
two levels
NA
Sensitivity
LLOQ = S/N ³ 5
Accuracy: 80-120 %
Precision: £ 20 %
MRL is confirmed by: Upper
PIR = (Mean + HR
PIR
)/forti fi ed
concentration × 100 £ 150 %
Lower PIR = (Mean − HR
PIR
)/
forti fi ed
concentration × 100 ³ 50 %
HR
PIR
= 3.963 S
LOD = S/N = 3
LOQ = the lowest
measureable
concentration of
actual sample with
interassay CV < 20 %
(continued)
