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Cited by 403Retinoids in leukemia and cellular processesAntioxidant Activity and Oxidative StressAnalytical Methods in Pharmaceuticals

Colour Reactions Attributed to Vitamin A

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Carr, Francis Howard, Price, Ernest Arthur·1926·Biochemical Journal
DOI 10.1042/bj0200497PMC PMC1251741
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Abstract

HAVING regard to the wide variation in the vitamin A activity of different cod-liver oils, it is a matter of practical importance to find the most ready means of assessing their relative activity.The long period of time occupied in carrying out the biological test renders this method not only tedious and expensive, but impractical from the point of view of industrial establishments requiring to accept or reject oils under conditions allowing at most one or two weeks for a decision.There is already good evidence that the well-known colour tests described by various workers, notably by Rosenheim and Drummond, may be expected ultimately to form a basis for a satisfactory chemical method of determining the vitamin value with great rapidity and approximate accuracy.All oils received in our laboratories for some time past have been submitted to these tests, in the first instance to the sulphuric acid test, and later to the trichloro- acetic acid and arsenic trichloride tests of Rosenheim and Drummond.Biological tests have been applied to some of these oils.We were naturally led, therefore, to make experiments with a view to improving the technique of the colour tests in order to find conditions whereby quantitative and strictly comparable readings may be obtained.This work has resulted in our utilising for the purpose yet another reagent of a similar character, namely, a solution of antimony trichloride in chloroform.By its use we have been enabled to determine standard conditions whereby direct readings of the intensity of the colour may be taken with the help of a tinto- meter.By following the conditions laid down observations made by different

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  • Vitamin A-containing solutions with Brønsted and Lewis acids change color from pale yellow to brilliant blue; the blue color is semistable with lifetime up to about 3 min in chloroform.

    “In the 1920s two groups164,165 made the discovery that vitamin A-containing solutions, in the presence of Brønsted and Lewis acids, undergo a color change from pale yellow (λmax ∼ 325 nm) to brilliant blue (λmax ∼ 600 nm). The blue color is semistable with an effective lifetime of up to ∼3 min when chloroform is used as a solvent.166”

    From Chemistry of the Retinoid (Visual) Cycle (2014) · cites this paper as [165]

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Authors
Carr, F. H., & Price, E. A.
Affiliations
The Laboratories of The British Drug Houses, Ltd., Graham Street, City Road, N. 1
ORCID
Carr, Francis Howard
Venue
Biochemical Journal
Publisher
Portland Press Ltd.
Published
1926-01-01
Volume
20
Issue
3
Pages
497-501
ISSN
0306-3283 (ISSN-L)
DOI
10.1042/bj0200497
PMC
PMC1251741
OpenAlex
W162928279
Cited by
401
References
2
Citations by year
2025: 1 · 2023: 2 · 2022: 3 · 2021: 2 · 2020: 3 · 2018: 1 · 2017: 3 · 2016: 2 · 2015: 1 · 2014: 2 · 2013: 7 · 2012: 5
FWCI
25.89
Type
journal article
Language
en
Open access
Locations
  • Biochemical Journal (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Retinoids in leukemia and cellular processes
  • Health Sciences › Medicine › Biochemistry › Antioxidant Activity and Oxidative Stress
  • Physical Sciences › Chemistry › Analytical Chemistry › Analytical Methods in Pharmaceuticals
Keywords
vitamin A, cod liver oil, color reaction, antimony trichloride, trichloroacetic acid, arsenic trichloride

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