SimultaneousDetermination of SevenWater SolubleVitamins inProducts byLC-MS/MS
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q)
IonRatioAcceptance criteria
i)
Inorder to ensuremethod specificity frommatrix tomatrix an ion ratio assessment of the native and
internal standard is applied to the data. The average ion ratio for each compound is established based
on the calibration standards analyzed to generate the calibration curve on the dayof analysis. The
tolerances presentedbelow are for both the native and labeled compounds.
TableA7. Overall precision and proposed ion ratio tolerances (STILLUNDEREVALUATION)
Folic
Acid
Biotin
Pantothenic
Acid
Niacin
Pyridoxine Riboflavin
Thiamine
Average
%RSD
7.9
5.6
2.0
2.5
2.0
5.0
4.8
%
Proposed
Tolerance
16.0
20.0
8.0
5.0
4.0
10.0
9.0
%Failure
3.8
5.9
0.5
1.1
2.7
3.8
3.8
r)
Internal StandardRecovery
i)
An internal standard can correct for variations in the extraction efficiencyduring sample preparation,
correct for errors or losses involumes during sample handling and in the case ofmass spectrometry
compensate for competitive ionization in the source caused by co-elutingmatrix components.
Despite the use of stable isotope labeled internal standards sourcematrix effects have been
demonstrated to impact the reported concentrations of selected analyte /matrix combinationswhen
the internal standard recovery is exceptionally lowor high. To address this issue an internal standard
recovery tolerance has beenproposed for each compound.
TableA8. Internal StandardRecovery targets and tolerances (STILLUNDEREVALUATION)
Folic
Acid
Biotin
Pantothenic
Acid
Niacin
Pyridoxine Riboflavin
Thiamine
Dilution
Rate
1-4
1-4
1-16
1-16
1-16
1-16
1-16
Average
SIIS%
Recovery
96
101
87
76
98
91
97
%RSD
6.3
9.7
17.2
14.9
6.5
18.4
10.7
Proposed
Tolerance
25
25
30
30
15
30
25
TargetLynx
Target
Value (%)
100
100
85
76
98
91
90
%False
Negative
0.9
1.4
2.4
2.4
2.8
8.1
3.6
BIO-03
FORWORKINGGROUP/ERPUSEONLY
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