AOAC SPIFAN Nutrients ERP Review (March 14, 2019)

2016.13 (Jan. 2019) Carot-02 MLT Report FOR ERP USE ONLY DO NOT DISTRIBUTE

(e) Lutein containing ca. 10% zeaxanthin .—USP Part No. 1370804. (f) β-Carotene system suitability reference standard .—USP Part No. 1065491. E. Standards Preparation Standard solution preparation is summarized in Table A and detailed below.

Note: Use glass volumetric pipettes and flasks for preparation of all standard solutions unless otherwise noted. Standard solution volumes may be scaled up or down provided good laboratory practices are followed. (a) Carotenoid stock solutions (10 000 - 20 000 μg/100 mL).— Weigh (to 0.01 mg) approximately 5 mg each of lutein, D(a) ; β-carotene, D(b) ; and apocarotenal, D(c) reference standard into separate 25 mL volumetric flasks. Add ca. 20 mL MTBE/Vitamin E, C(m) , to each, sonicate 2-3 min, and dilute to volume with MTBE/Vitamin E. Weigh (to 0.01 mg) approximately 5 mg lycopene, D(d) reference standard into a 50 mL volumetric flask. Add ca. 40 mL THF/Vitamin E, C(n) , sonicate 2-3 min, and dilute to volume with THF/Vitamin E. Store stock solutions in glass vials at -20°C for up to 6 months and check their purity each time new standard solutions are made from them. When taken from the freezer, stock solutions should be sonicated 2 min and vortexed to bring all carotenoids into solution. (b) Standard measuring solutions for UV-visible spectroscopy potency check (200 μg/100 mL).— Transfer 1.0 mL lutein and β-carotene standard stock solutions, E(a) , to separate 100 mL volumetric flasks and dilute each to volume with MTBE. Transfer 2.0 mL lycopene standard stock solution, E(a) , to a 100 mL volumetric flask and dilute to volume with hexane. Immediately measure by UV-visible spectroscopy and calculate purity according to section H(a) .

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