Abstract
1. There were little differences between BP 1960 and BP 1963 methods on the values of the all-trans vitamin A acetate solution.
2. The values of the mixed sample solutions containing both pure all-trans vitamin A acetate and pure neovitamin A acetate estimated by BP 1963 method were a little higher than those by BP 1960 method, the latters being closer to the calculated biological potencies.
3. The values of vitamin A oil standard containing all-trans vitamin A only estimated by JP VII revised method and USP XVI method were 1 to 1.5% lower than those by BP 1960 and BP 1963 methods because of the loss of vitamin A in the preparation of unsaponifiable matters.
4. The values of the samples containing all-trans vitamin A and neovitamin A (oleovitamin A and fish liver oils) estimated by BP 1963 method were 1 to 4% higher than those by JP VII revised method, USP XVI and BP 1960 methods. This might be due to the influence of neovitamin A.
5. According to the results of this and the previous reports, it may be concluded that JP VII revised method is the most desirable one for the determination of all-trans vitamin A and of a mixture of all-trans vitamin A and neovitamin A, followed by USP XVI and BP 1960 methods.