SimultaneousDetermination of SevenWater SolubleVitamins inProducts byLC-MS/MS
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EDTA. Mix by stirringon amagnetic stir plate until both theEDTA andpotassiumphosphate
dibasic is completelydissolved.
iv)
Weigh40.0± 0.2ggrams ofmetaphosphoric acid into a tarredweighingvessel andquantitatively
transfer to the 2000-mL beaker containing approximately1800mL laboratorywater, EDTA, and
potassiumphosphate dibasic. Mixby stirringon amagnetic stir plate until themetaphosphoric acid is
completelydissolved.
v)
Adjust the pH of the solution topH5.00±0.02using40% potassiumhydroxide or 85% phosphoric
acid. Quantitatively transfer the solution to a 2000-mL volumetric flask and dilute to volumewith
laboratorywater. Expiration48 hour
i)
NativeStockSolutions
i)
FolicAcidStockSolution;ApproximateConcentration: 250µg/mLStore at 2-8ºC. Expiration: 4
months.
(1) Weigh approximately62.5± 0.5mgof folic acid into aweighing funnel or other appropriate
weighingvessel. Quantitatively transfer to a 250-mL volumetric flaskwith0.3% ammonium
hydroxide solution. Aftermixing thoroughly, dilute tovolumewith0.3% ammoniumhydroxide
solution andmixwell. Store
ii)
VitaminStandardStockMixture (VSSM). Store refrigerated (2˚-8˚C). Expiration: 4months.
(1)
Accuratelyweigh the indicated amounts for the following standards using separateweighing
funnels or other appropriateweighingvessel and quantitatively transfer to a 100-mL volumetric
flaskusingphosphate buffer (pH5):
(a)
Niacinamide: 70.5± 0.5mg
(b)
Calciumpantothenate: 46.0± 0.5mg
(c)
Thiamine hydrochloride: 10.5± 0.2mg
(d)
Riboflavin: 7.0± 0.2mg
(e)
PyridoxineHydrochloride: 10.8±0.2mg
(f)
Biotin: 6.0± 0.2mg
(2)
Dilute to volumewith phosphate buffer (pH5) solution.
(3)
Heat and slowly stir until the standards have completelydissolved (riboflavin andbiotin dissolve
more slowly) and the solution is clear. Do not heat the solution formore than40minutes anddo
not exceed 90°C
j)
Internal StandardSolutions
i)
13
C
5
-FolicAcidStockSolution (ApproximateConcentration: 50µg/mL)
(1) Weigh 5.0± 0.1mg into a tarredweighingvessel. Quantitatively transfer to a 100-mL
volumetric flaskusing0.3% ammoniumhydroxide solution and dilute tovolumewith0.3%
ammoniumhydroxide solution. Mixwell and transfer to a 100-mL amber bottle andStore
refrigerated (2˚-8˚C).
(2)
Expiration: Until exhausted or evidence of contamination.
ii)
13
C
5
-BiotinStockSolution (ApproximateConcentration: 50µg/mL)
(1) Weigh5.0mg± 0.1mg into a tarredweighingboat. Quantitatively transfer to a 100-mL
volumetric flaskwith50%methanol anddilute to volumewith50%methanol. Mixwell and
transfer to 100-mL amber bottle andStore refrigerated (2˚-8˚C).
(2)
Expiration: Until exhaustedor evidence of contamination.
iii)
13
C
3
,
15
N-PantothenicAcidStockSolution (ApproximateConcentration: 100µg/mL)
(1) Weigh5.0± 0.1mg into a tarredweighingvessel. Quantitatively transfer to a 50-mL volumetric
flaskwith laboratorywater and dilute to volumewith laboratorywater. Mixwell and transfer to a
100-mL amber bottle andStore refrigerated (2˚-8˚C).
(2)
Expiration: Until exhaustedor evidence of contamination.
iv)
2
H
4
-NiacinStockSolution (ApproximateConcentration: 560µg/mL)
BIO-03
FORWORKINGGROUP/ERPUSEONLY
DONOTDISTRIBUTE
