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Thompson et al.:
J
ournal of
AOAC I
nternational
V
ol.
98, N
o.
6, 2015
1717
Table 3. Calibration standards and PLOQ
Na, mg/L Mg, mg/L P, mg/L K, mg/L Ca, mg/L Mn, mg/L Fe, mg/L Cu, mg/L Zn, mg/L Cr,
μ
g/L Se,
μ
g/L Mo,
μ
g/L
Cal Blk
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Cal Std 1
0.500 0.200 0.500 1.00
1.00 0
.00500 0.0500 0.00500 0.0200 0.800 0.400 0.800
Cal Std 2
2.50
1.00
2.50
5.00
5.00 0.0250 0.250 0.0250 0.100 4.00
2.00
4.00
Cal Std 3
10.0
4.00
10.0
20.0
20.0 0.100 1.00 0.100 0.400 16.0
8.00
16.0
Cal Std 4
20.0
8.00
20.0
40.0
40.0 0.200 2.00 0.200 0.800 32.0
16.0
32.0
PLOQ, mg/L
a
0.25
0.10
0.25
0.50
0.50 0.0025 0.025 0.0025 0.010
0.4
0.2
0.4
PLOQ, mg/100 g
b
1.3
0.50
1.3
2.5
2.5
0.013
c
0.13
c
0.013
c
0.050
20
10
20
SMPRs, mg/100 g
d
10
3
15
10
20
0.001 0.01 0.001
0.1
20
10
20
a
Units are µg/L for Cr, Mo, and Se.
b
mg of Na, Mg, P, K, Ca, Mn, Fe, Cu, or Zn/100 g of reconstituted final product, or µg of Cr, Mo, or Se/kg of reconstituted final product for a typical
dilution factor of 50:1.0 g RTF product or reconstituted powder/50 mL final volume.
c
Note that the PLOQs for Mn, Fe, and Cu (in boldface) do not meet SMPR requirements.
d
mg of Na, Mg, P, K, Ca, Mn, Fe, Cu, or Zn/100 g of reconstituted final product, or µg of Cr, Mo, or Se/kg of reconstituted final product.
Table 4. Summary of results for RSD
ip
in 11 SPIFAN matrixes tested in duplicate over 8 days (results were collected in
terms of “per kg” as-is for powders in this case, rather than the default SPIFAN units of mg/100 g or μg/100 g reconstituted
product)
Matrix/SPIFAN No.
Parameter
Na
Mg
P
K
Ca
Cr
a
Mn
Fe
Cu
Zn
Se
a
Mo
a
A-RTF, high fat
00406RF00
b
Mean, mg/kg 1390 398 1010 2360 888 141 4.80 21.5 2.37 27.9 133 193
RSD, % 2.0 1.8
2.9
1.7
9.4
1.8
4.8
3.6
3.0
1.4
3.6
2.6
A-RTF, high protein
00414RF00
Mean, mg/kg 1020 330 951 1560 983 130 4.22 18.7 1.81 22.0 92.6 154
RSD, % 1.9 3.4
3.4
3.9
2.8
2.9
2.1
3.4
3.0
2.4
3.0
3.2
AP, milk protein
11750017V3
c
Mean, mg/kg 2270 430 2140 5810 2820 142 5.30 43.8 11.5 52.4 219 294
RSD, % 2.2 3.3
2.4
1.7
2.3
5.0
2.6
4.0
3.3
2.6
2.8
4.9
AP, low fat
00394RF00
Mean, mg/kg 2070 1130 2710 5060 2740 428 14.0 59.8 6.34 62.1 268 565
RSD, % 2.8 2.9
1.8
2.1
2.7
1.3
2.7
3.5
3.3
2.6
3.2
3.0
PP
00412RF00
d
Mean, mg/kg 1460 741 3490 5500 3790 271.9 7.62 57.7 5.15 37.6 213 261
RSD, % 2.6 2.5
2.0
2.5
1.8
1.3
1.4
3.2
3.7
1.7
2.9
5.1
IP, elemental
00403RF00
e
Mean, mg/kg 2410 489 4560 7970 6310 215 4.67 105 7.20 64.6 209 160
RSD, % 3.0 3.3
2.4
3.1
2.2
6.3
1.3
1.9
1.7
2.1
2.8
7.5
IP, milk
D04HTCVV
Mean, mg/kg 1870 565 2800 6750 4690 44.3 1.05 116 5.43 65.9 230 159
RSD, % 3.2 2.9
1.7
3.3
2.5
7.7
2.0
2.0
4.9
1.5
3.8
8.2
IP, milk, partially
hydrolyzed
1172572116
Mean, mg/kg 1560 377 2310 6450 4190 21.4 1.05 83.7 4.90 43.4 239 184
RSD, % 1.8 2.6
4.4
1.1
2.2 20.2 2.6
3.1
3.9
2.6
2.7
4.0
IP, soy, partially
hydrolyzed
117257651Z
Mean, mg/kg 2470 604 3950 7400 6480 53.6 2.30 111 4.88 49.2 242 297
RSD, % 2.9 2.9
3.6
2.2
2.2
9.2
2.6
2.5
3.9
1.8
4.1
3.6
I-RTF, soy
E29JVLV
f
Mean, mg/kg 2301.3 726 4250 7540 6470 72.5 3.31 114 5.40 73.9 223 328
RSD, % 2.4 2.8
5.0
2.6
3.5
5.2
2.3
2.4
4.1
2.3
3.3
4.5
I-RTF, milk
control
Mean, mg/kg 179 59.4 298 1000 598 7.61 0.153 14.3 0.579 7.17 29.6 16.9
RSD, % 2.2 3.1
4.3
3.0
4.5 52.7 2.9
4.3
3.5
2.1
2.9 10.0
a
Concentrations in μg/kg.
b
A-RTF = Adult ready-to-feed formula.
c
AP = Adult powder formula.
d
PP = Pediatric powder formula.
e
IP = Infant powder formula.
f
I-RTF = Infant ready-to-feed formula.
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