Beta Carotene
(bay' ta kar' oh teen).
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536.87
,-Carotene.
all-trans-
-Carotene.
(all-E)-1,1¢-(3,7,12,16-Tetramethyl-1,3,5,7,9,11,13,15,17-octadecanonaene-1,18-diyl)bis[2,6,6-trimethylcyclohexene]
[7235-40-7].» Beta Carotene contains not less than 96.0 percent and not more than 101.0 percent of C40H56.
Packaging and storage—
Preserve in tight, light-resistant containers.
Identification—
A:
Determine the absorbances of Assay preparation B at 455 nm and at 483 nm: the ratio of the absorbance at 455 nm to that at 483 nm is between 1.14 and 1.18.
B:
Determine the absorbance of Assay preparation B at 455 nm and that of Assay preparation A at 340 nm: the ratio of the absorbance at 455 nm to that at 340 nm is not less than 1.5.
Melting range 
741
:
between 176
and 182, with decomposition.
741:
between 176 and 182, with decomposition.
Loss on drying 731—
Dry it in vacuum over phosphorus pentoxide at 40 for 4 hours: it loses not more than 0.2% of its weight.
731—
Dry it in vacuum over phosphorus pentoxide at 40 for 4 hours: it loses not more than 0.2% of its weight.
Residue on ignition 281:
not more than 0.2%, 2 g of specimen being used.
281:
not more than 0.2%, 2 g of specimen being used.
Heavy metals, Method II 231:
0.001%.
231:
0.001%.
Assay—
[note—Perform this procedure in subdued light, using low-actinic glassware. ]
Assay preparation A—
Transfer about 50 mg of Beta Carotene, accurately weighed, to a 100-mL volumetric flask, dissolve in 10 mL of acid-free chloroform, dilute with cyclohexane to volume, and mix. Pipet 5 mL of this solution into a 100-mL volumetric flask, dilute with cyclohexane to volume, and mix.
Assay preparation B—
Pipet 5 mL of Assay preparation A into a 50-mL volumetric flask, dilute with cyclohexane to volume, and mix.
Procedure—
Determine the absorbance of Assay preparation B, at the wavelength of maximum absorbance at about 455 nm, with a suitable spectrophotometer, using cyclohexane as the blank. Calculate the quantity, in mg, of C40H56 in the portion of Beta Carotene taken by the formula:
20,000 AX / 250
in which AX is the absorbance of Assay preparation B; and 250 is the absorptivity of pure beta carotene.
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Huy T. Dinh, M.S.
Scientific Liaison 1-301-816-8594 |
(DS2010) Monographs - Dietary Supplements |
USP35–NF30 Page 2333
Pharmacopeial Forum: Volume No. 36(6) Page 1498