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Abbott Nutrition Division
Simultaneous Determination of Total Vitamin B
6,
B
2,
B
3
and B
1
in Infant
Formula Products by LC-MS/MS Using Enzymatic Digestion
9.
Filter an aliquot of the sample extract into an amber autosampler vial using a 0.20 µm PTFE syringe
filter.
NOTE: Ensure that the filtered sample solution is clear. If the filter fails the solution in the
autosampler vial will appear cloudy. If this is observed discard this sample and filter
another aliquot of the sample into a clean autosampler vial.
Samples are stable for up to 48 hours at room temperature. Working standard solutions and samples
must be tested as a complete set if reanalysis is required. It is recommended that the autosampler
vials be recapped if reanalysis is anticipated.
F.
CALCULATIONS AND EXAMPLES
1.
All calculations are performed using MassLynx software, current revision (Version 4.1, or later) fitted
with Target Lynx data processing software.
2.
Analyte concentrations in product samples are calculated by comparison of calculated response ratios
for the analyte in the sample to that calculated for the calibration standards using least squares
regression. Response ratios used for the linear regression are calculated using the ratio of the response
of the analyte to that of its internal standard. This ratio is then plotted against the concentration of the
standard.
3.
Vitamin Stock Solutions – Native Stock Solutions
[ ]
Vol
PSMW
Vit
s
000 ,1
××× ×
=
Where:
[Vit]: Vitamin Standard Solution Concentration, in
m
g/mL
W
S
: Weight of Standard, in mg
S: Stoichiometric correction factor (0.8227, 0.8209, and 0.6976 for Pryridoxine,
Pyridoxal, and Pyridoxamine respectively).
M: Moisture content correction factor for the Standard (per AN-RS Method 1.57), (used
for Thiamin)
100
)
(% 100
Moisture
M
− −
=
P: Purity of standard as defined by the manufacturer
1,000: Units Conversion Factor, mg to µg
Vol: Solution Volume, in mL
a)
Pyridoxine (PN) Stock Solution Concentration Calculation
[ ]
10
100
000 ,1
8227 .0
×× × =
××
×
=
PM W
mL
P
W
PN
PN
PN
S
38
BVIT-02
FOR ERP/WORKING GROUP USE ONLY
DO NOT DISTRIBUTE