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» Zein is a prolamine derived from corn (Zea mays Linné [Fam. Gramineae]).
Packaging and storage— Preserve in tight containers.
A: Dissolve about 0.1 g in 10 ml of 0.1 N sodium hydroxide, and add a few drops of cupric sulfate TS. Warm in a water bath: a purple color develops.
B: To a test tube containing 25 mg of Zein add 1 mL of nitric acid. Agitate vigorously: the solution becomes light yellow. Further addition of about 10 mL of 6 N ammonium hydroxide produces an orange color.
C: It is insoluble in water, but 1 g of it in 10 mL of a mixture of isopropyl alcohol and water (85:15), at a temperature of about 37, yields a clear to cloudy solution.
Microbial limits 61 The total bacterial count does not exceed 1000 cfu per g, and the tests for Salmonella species and Escherichia coli are negative.
Loss on drying 731 Dry it at 105 for 2 hours: it loses not more than 8.0% of its weight.
Residue on ignition 281: not more than 2.0%.
Nitrogen content— Proceed as directed under Nitrogen Determination, Method I 461: the nitrogen content is not less than 13.1% and not more than 17.0%, on the dried basis.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Auxiliary Information— Staff Liaison : Hong Wang, Ph.D. , Senior Scientific Associate
Expert Committee : (EM205) Excipient Monographs 2
USP29–NF24 Page 3461
Phone Number : 1-301-816-8351