376 / 670
(d)
Calculate the response factor (RF) for each carotenoid based on average peak areas in the mixed
carotenoid WS:
RF
L
= (C
L
/C
A
) x (A
A
/A
L
)
Where C
L
= the concentration of all-trans-lutein in the mixed carotenoid WS (μg/100 mL)
C
A
= the concentration of apocarotenal in the mixed carotenoid WS (μg/100 mL)
A
A
= the peak area of apocarotenal in the mixed carotenoid WS (AU)
A
L
= the peak area of all-trans lutein in the mixed carotenoid WS (AU)
(e)
Calculate the mass of apocarotenal (M
A
), in μg, added to the test samples:
M
A
= (C
A
x V
A
) x (4/50)
Where C
A
= the concentration of apocarotenal in the apocarotenal WS (μg/100 mL)
V
A
= the volume of ISTD solution added to each sample, in mL
4 = the volume of apocarotenal WS used in the ISTD solution, in mL
50 = the total volume of ISTD solution made, in mL
(f)
Calculate the contents of all-
trans
lutein and
cis
isomers of lutein in the test samples:
L
trans
= RF
L
x (M
A
/M
S
) x (A
L
/A
A
) x 100
Where L
trans
= the all-
trans
lutein in the sample (μg/100 g)
RF
L
= the response factor for all-
trans
-lutein
M
A
= the mass of apocarotenal added to the test sample, in μg
M
S
= the sample weight, in g
A
L
= the peak area of all-
trans
-lutein in the sample chromatogram (AU)
A
A
= the peak area of apocarotenal in the sample chromatogram (AU)
L
cis
= RF
L
x (M
A
/M
S
) x ([A
13cisL
+ A
13’cisL
+ A
XcisL
]/A
A
) x 100
Where L
cis
= the
cis
isomers of lutein in the sample (μg/100 g)
RF
L
= the response factor for all-
trans
-lutein
M
A
= the mass of apocarotenal added to the test sample, in μg
M
S
= the sample weight, in g
A
13cisL
= the peak area of 13-
cis
lutein in the sample chromatogram (AU)
A
13’cisL
= the peak area of 13’-
cis
lutein in the sample chromatogram (AU)
A
XcisL
= the peak area of unidentified
cis
isomers of lutein in the sample chromatogram
(AU)
A
A
= the peak area of apocarotenal in the sample chromatogram (AU)
Carot-02 (February 2016)
FOR ERP USE ONLY
DO NOT DISTRIBUTE