Packaging and storage
Preserve in tight, light-resistant containers.
Label the Capsules to indicate the form in which the vitamin is present, and to indicate the vitamin A activity in terms of the equivalent amount of retinol in mg. The vitamin A activity may be stated also in USP Units per Capsule, on the basis that 1 USP Vitamin A Unit equals the biological activity of 0.3 µg of the all-trans isomer of retinol.
45 minutes, determined using 0.05 M
acetate buffer, prepared by mixing 2.99 g of sodium acetate and 1.66 mL of glacial acetic acid with water to obtain 1000 mL of solution having a pH of 4.5 ± 0.05, maintained at 37 ± 2
as the immersion fluid.
The contents of Capsules respond to the tests for Identification for vitamin A and meet the requirements of the test for Absorbance ratio under Vitamin A.
Using not less than 5 Capsules, proceed as directed under Vitamin A Assay 571
. Calculate the content of retinol (C20
O) in mg and in USP Vitamin A Units per Capsule.