AOAC SPIFAN Nutrients ERP (December 7, 2022)

Fluor-06 (SLV) 10-2022 FOR ERP USE ONLY DO NOT DISTRIBUTE

5 x10

+EI TIC Scan 20220920-3.D

2.8

8.108

TMFS

2.6

2.4

7 x10

+EI TIC Scan 20220920-3.D

hexamethyldisiloxane

2.2

3.4

2

3.2

17.302

1.8

3

pentane

1.6

propanal

2.8

1.4

2.6

9.720

acetone

1.2

2.4

1

2.2

7.561

0.8

2

7.397

0.6

trimethylsilanol

10.914

0.879

1.8

0.4

1.6

furan

0.2

DCM

1.590

15.974

1.4

0

7.5

8

8.5

9

9.5

10

1.2

Counts vs. Acquisition Time (min)

1

Air: mainly Nitrogen oxygen

0.8

12.352

0.6

0.4

12.949

0.2

19.452

13.815

11.884

8.108

15.471

14.626

9.720

7.561

6.297

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

Counts vs. Acquisition Time (min)

Figure 6. Entire GC-MS chromatogram of sample NIST10175 with the inset showing the enlarged area where TMFS elutes, including the identities of the different compounds measured. The abbreviation of DCM stands for dichloromethane.

In another experiment to study selectivity, other sodium halogen salts (NaCl, NaBr and NaI) were subjected to the same procedure as NaF. In none of the chromatograms any peaks related to these halides were found (results not shown).

5.4 Recovery

Dry powders (standard procedure) The recovery was determined from the 6-fold analysis of QC samples spiked at four different levels. The results are shown in Table 7. The recovery required should be 90–110% for the highest level, and 80–120% for the other levels. In all cases the results found are within these limits. Table 7. Recoveries (%) of spiked QC samples at four different levels. Day 1 QC-LOQ Day 2 QC-LOW Day 3 QC-MED Day 4 QC-HIGH Day 5 QC-mix* Day 6 QC-mix* 1 94.5 104.9 94.3 94.9 97.0 (LOQ) 96.3 (LOQ) 2 94.3 104.3 92.9 96.0 99.8 (LOW) 94.6 (LOW) 3 97.2 104.4 93.6 95.7 92.0 (MED) 84.9 (MED) 4 94.5 106.1 93.7 96.5 97.8 (HIGH) 93.1 (HIGH) 5 92.0 104.7 92.7 96.2 6 97.6 104.1 93.2 95.5 Average (%) 95.0 104.8 93.4 95.8 96.2 92.0 RSD (%) 2.2 0.7 0.6 0.6 4.0 6.1 * Duplicate analyses.