5 / 76
3
3.2
Precision and Accuracy (Trueness)
Three samples were selected for precision studies:
-
Standard Reference Material (SRM) 1849a (National Institute of Standards and Technology
(NIST)).
-
Reference sample infant formula 04-1426 (International Bureau for Analytical Studies
(Bipea)).
-
Infant formula powder partially hydrolysed soy based (4, SPIFAN).
SRM 1849a and infant formula Bipea 04-1426 were selected for accuracy studies.
Samples were analysed in duplicate on six different days by two analysts.
Results are reported in Tables 4, 5 and 6.
Table 4: SRM 1849a: precision and accuracy (trueness).
SD(r)
RSD
r
SD(iR)
RSD
iR
RSD
r
Accuracy
His
315
319
5.62
2.69 0.8% 5.94 1.9% 101.2% yes
yes
Tau
36.6
35.5
0.76
0.42 1.2% 0.82 2.3% 97.0% yes
yes
Ser
720
708
8.91
5.16 0.7% 9.63 1.4% 98.4% yes
yes
Arg
400
404
14.31
3.2 0.8% 14.49 3.6% 100.9% yes
yes
Gly
241
249
1.47
1.5 0.6% 1.82 0.7% 103.3% yes
yes
Asp
1070
1089
16.17 8.24 0.8% 17.19 1.6% 101.7% yes
yes
Glu
2590
2675
80.1 21.71 0.8% 81.56 3.0% 103.3% yes
yes
Thr
640
644
9.07
5.08 0.8% 9.76 1.5% 100.6% yes
yes
Ala
455
448
5.74
3.48 0.8% 6.25 1.4% 98.5% yes
yes
Pro
1195
1181
11.69 7.24 0.6% 12.76 1.1% 98.8% yes
yes
Lys
1010
1054
10.74 8.73 0.8% 12.39 1.2% 104.3% yes
yes
Tyr
510
577
6.65
4.49 0.8% 7.37 1.3% 113.1% yes
no
Cys2
128.6
133
4.94
2.17 1.6% 5.17 3.9% 103.4% yes
yes
Met
n/a
467
5.53
3.98 0.9% 6.21 1.3% n/a
yes
n/a
Val
760
819
35.64
6.6 0.8% 35.95 4.4% 107.7% yes
yes
Ile
660
705
10.11 6.19 0.9% 11.01 1.6% 106.9% yes
yes
Leu
1261
1241
26.61 9.83 0.8% 27.5 2.2% 98.4% yes
yes
Phe
580
586
7
4.34 0.7% 7.64 1.3% 101.1% yes
yes
Meet SMPR spec.
Analyte
Ref. val.
[mg/100g]
Average
[mg/100g]
Precision
Recovery
SD(b)
AMINO-01
FOR ERP/WORKING GROUP USE ONLY
DO NOT DISTRIBUTE