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Analysis of Vitamin D
2
and Vitamin D
3
by LC-MS/MS in Milk
Powders, Infant Formulas, and Adult Nutritionals
Page 7 of 10
d
CE = collision energy
e
CXP = collision cell exit potential
Mass Spectrometry: Compound Parameters (Vitamin D
3
instrument method only)
Vitamin D
3
Type
a
Precursor
ion
(
m/z
)
Product
ions
(
m/z
)
DP
c
(V)
EP
d
(V)
CE
e
(V)
CXP
e
(V)
Dwell
time
(ms)
Analyte quantifier ion
560.2
298.0
151
10
21
18
120
Analyte qualifier ion
560.2
279.8
37
18
80
Internal standard quantifier ion
566.2
298.0
21
18
120
Internal standard qualifier ion
566.2
279.8
37
18
80
a
Analyte = vitamin D
3
-PTAD adduct, Internal standard ion = d6-vitamin D
3
-PTAD adduct
b
DP = declustering potential
c
EP = entrance potential
d
CE = collision energy
e
CXP = collision cell exit potential
Calculation and Reporting
Concentration of stable isotope labelled vitamin D
2
in stock standard
SILD
2
SS
:
10000
x
1%
1cm
max)
abs(
λ
2
D2conc
2
E
SS SILD
SS SILD
where:
SILD
2
SS
D2conc
= concentration of SIL d6-vitamin D
2
in stock standard (
units
: μg mL
-1
)
SILD
2
SS
abs(
λ
max)
= UV absorbance of stock standard at 265 nm (
units
: none)
= extinction coefficient for vitamin D
2
in ethanol [461] (
units
: dL g
-1
cm
-1
)
10000 = concentration conversion factor (
units
: g dL
-1
to μg mL
-1
)
Concentration of stable isotope labelled vitamin D
3
in stock standard
SILD
3
SS
:
10000
x
1%
1cm
max)
abs(
λ
3
D2conc
3
E
SS SILD
SS SILD
where:
SILD
3
SS
D3conc
= concentration of SIL d6-vitamin D
3
in stock standard (
units
: μg mL
-1
)
SILD
3
SS
abs(
λ
max)
= UV absorbance of stock standard at 265 nm (
units
: none)
= extinction coefficient for vitamin D
3
in ethanol [485] (
units
: dL g
-1
cm
-1
)
10000 = concentration conversion factor (
units
: g dL
-1
to μg mL
-1
)
Concentration of stable isotope labelled vitamin D
2
in internal standard
SILIS
:
1000
10
1.0 x
SS SILD
SILIS
D3conc
2
D2conc
u
where:
SILIS
D2conc
= concentration of SIL d6-vitamin D
2
in internal standard (
units
: ng mL
-1
)
SILD
2
SS
D2conc
= concentration of SIL d6-vitamin D
2
in stock standard (
units
: μg mL
-1
)
1000 = concentration conversion factor (
units
: μg mL
-1
to ng mL
-1
)
Concentration of stable isotope labelled vitamin D
3
in internal standard
SILIS
:
1%
1cm
E
1%
1cm
E
VitD-18 (February 2016)
FOR ERP USE ONLY
DO NOT DISTRIBUTE