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Chromium Picolinate
» Chromium Picolinate contains not less than 98.0 percent and not more than 102.0 percent of C18H12N3O6Cr, calculated on the dried basis.
Packaging and storage
Preserve in tight containers.
Identification
B:
To 5 mL of a solution (1 in 250) in a test tube add 1 mL of 5 N sodium hydroxide and 10 drops of 30% hydrogen peroxide, and heat gently for about 2 minutes: a yellow color develops.
Loss on drying
Chloride
Sulfate
Assay
Standard stock solution
Transfer about 0.283 g of potassium dichromate, previously dried at 120
Standard preparations
Separately transfer 1.0 mL and 2.0 mL of the Standard stock solution to 100-mL volumetric flasks, and transfer 1.5 mL and 2.0 mL of the Standard stock solution to separate 50-mL volumetric flasks. Add 1.0 mL of nitric acid to each flask, dilute the contents of each flask with water to volume, and mix. These Standard preparations contain 1.0, 2.0, 3.0, and 4.0 µg of chromium per mL, respectively.
Assay preparation
Transfer about 200 mg of Chromium Picolinate, accurately weighed, to a 500-mL volumetric flask, and add 25 mL of water. Slowly add 10 mL of nitric acid, and boil for 10 minutes with constant swirling. Cool the solution, dilute with water to volume, and mix. Filter a portion of the solution, and transfer 5 mL of the filtrate to a 100-mL volumetric flask. Add 1 mL of nitric acid, dilute with water to volume, and mix.
Procedure
Concomitantly determine the absorbances of the Standard preparations and the Assay preparation at the chromium emission wavelength of 357.9 nm, with a suitable atomic absorption spectrophotometer (see Spectrophotometry and Light-Scattering
(418.31 / 51.996)(10C)
in which C is the concentration, in µg per mL, of chromium in the Assay preparation; 418.31 is the molecular weight of chromium picolinate; and 51.996 is the atomic weight of chromium.
Auxiliary Information
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USP32NF27 Page 982
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