Vitamin E Preparation
»Vitamin E Preparation is a combination of a single form of Vitamin Ewith one or more inert substances.It may be in a liquid or solid form.It contains not less than 95.0percent and not more than 120.0percent of the labeled amount of Vitamin E.Vitamin E Preparation labeled to contain a dl-form of Vitamin Emay contain also a small amount of a d-form occurring as a minor constituent of an added substance.
Packaging and storage— Preserve in tight containers,protected from light.Protect Preparation containing d-or dl-alpha tocopherol with a blanket of an inert gas.
Labeling— Label it to indicate the chemical form of Vitamin Epresent,and to indicate whether the d-or the dl-form is present,excluding any different forms that may be introduced as a minor constituent of the vehicle.Designate the quantity of Vitamin Epresent.
Identification—
Test solution— Proceed with the extraction and isolation of the residue obtained by hydrolysis as directed for Test solution for alpha tocopheryl acid succinatein the Identificationtest under Vitamin E.Immediately dissolve the residue in dehydrated alcohol,transfer to a 250-mLvolumetric flask,dilute with dehydrated alcohol to volume,and mix.
A: To 10mLof Test solutionadd,with swirling,2mLof nitric acid,and heat at about 75for 15minutes:a bright red or orange color develops.
B: Transfer an accurately measured volume of Test solution,equivalent to about 100mg of the test specimen,to a separator,and add 200mLof water.Proceed as directed in Identificationtest Bunder Vitamin E,beginning with “Extract first with 75mL.”
C: The retention time of the major peak in the chromatogram of the Assay preparationis the same as that of the Standard preparation,both relative to the internal standard,as obtained in the Assay.
Acidity—
Liquid forms of Vitamin E Preparation— Dissolve 1.0g in 25mLof a mixture of equal volumes of alcohol and ether (which has been neutralized to phenolphthalein with 0.1Nsodium hydroxide),add 0.5mLof phenolphthalein TS,and titrate with 0.10Nsodium hydroxide until the solution remains faintly pink after shaking for 30seconds:not more than 1.0mLof 0.10Nsodium hydroxide is required.
Assay— Proceed with Vitamin E Preparation as directed for the appropriate Assayunder Vitamin E,substituting the following for the Assay preparation.
Assay preparation— [NOTE—Use low-actinic glassware.]
If the Preparation is in the liquid form ,transfer an accurately weighed portion of Vitamin E Preparation,equivalent to about 50mg of the specified form,to a 50-mLvolumetric flask,dissolve in Internal standard solution,dilute with Internal standard solutionto volume,and mix.
If the Preparation is in the solid form ,transfer an accurately weighed portion of Vitamin E Preparation,equivalent to about 50mg of Vitamin E,into a flask suitable for refluxing.Add about 5mLof water,and heat on a water bath at 60for 10minutes.Add about 25mLof alcohol,and reflux for 30minutes.Cool,and transfer to a separator with the aid of 50mLof water and 50mLof ether.Shake vigorously,allow the layers to separate,and collect each in individual separators.Extract the aqueous layer with two 25-mLportions of ether,combining the extracts with the original ether layer.Wash the combined ether extracts with one 25-mLportion of water,filter the ether solution through 1g of granular anhydrous sodium sulfate,and evaporate the ether solution on a water bath,controlled at a temperature that will not cause the ether solution to boil over,with the aid of a stream of nitrogen.Remove the container from the water bath when 5mLremains,and complete the evaporation without the application of heat.Dissolve the residue in 50.0mLof Internal standard solution,and mix.
Auxiliary Information— Staff Liaison:Lawrence Evans,III,Ph.D.,Scientist
Expert Committee:(DSN)Dietary Supplements:Non-Botanicals
USP28–NF23Page 2030
Phone Number:1-301-816-8389