An Efficient Solid-Phase Extraction-Based Liquid Chromatography Method to Simultaneously Determine Diastereomers α-Tocopherol, Other Tocols, and Retinol Isomers in Infant Formula
Table 2
Accuracy and precious in spiked infant formula samples (n = 6).
Analyte
Blank(a) (mg kg−1)
Spiking level 1(b)
Spiking level 2
Spiking level 3
Recovery (SD) %
RSD%
Recovery (SD) %
RSD%
Recovery (SD) %
RSD%
All-trans-retinol
2.25 (0.10)
95.31 (3.46)
3.63
82.49 (3.18)
3.85
82.54 (3.21)
3.89
13-cis-retinol
0.74 (0.10)
74.66 (2.72)
3.64
95.12 (9.80)
10.30
98.63 (9.61)
9.74
9-cis-retinol
0.39 (0.10)
112.92 (5.71)
5.05
96.40 (6.27)
6.50
97.23 (4.38)
4.51
DL-α-tocopherol
114.19 (2.02)
103.22 (4.19)
3.9
91.34 (2.59)
2.86
85.70 (1.07)
1.25
D-α-tocopherol
69.85 (2.33)
104.12 (6.20)
5.68
93.35 (2.65)
2.84
87.24 (0.84)
0.97
D-β-tocopherol
1.26 (0.15)
92.22 (1.41)
1.53
89.29 (1.49)
1.67
91.62 (0.59)
0.65
D-γ-tocopherol
23.14 (0.92)
92.70 (9.75)
10.52
90.93 (5.28)
5.81
90.90 (3.57)
3.92
D-δ-tocopherol
10.42 (0.47)
81.15 (6.67)
8.22
84.14 (4.28)
5.08
83.16 (2.24)
2.69
D-α-tocotrienol
2.42 (0.00)
76.38 (4.03)
5.28
90.31 (2.69)
2.97
89.53 (2.70)
3.02
D-β-tocotrienol
ND
109.38 (9.95)
9.10
97.18 (4.21)
4.33
95.35 (2.90)
3.05
D-γ-tocotrienol
1.07 (0.00)
79.81 (0.16)
0.20
82.03 (4.49)
5.47
83.83 (1.90)
2.27
D-δ-tocotrienol
0.78 (0.00)
82.98 (3.38)
4.07
85.15 (1.00)
1.18
85.92 (1.16)
1.35
(a)ND represents mass fraction of the analyte in sample was lower than LOD. (b)Spiking concentrations were based 0.75-, 1.5-, and 3-folds on the content of analytes in infant formula sample, which was mainly calculated based on the content of D-α-tocopherol.
