Pregelatinized Modified Starch
» Pregelatinized Modified Starch is Modified Starch that has been chemically or mechanically processed, or both, to rupture all or part of the granules to produce a product that swells in cold water.
A: Prepare a 2% (w/w) sodium hydroxide solution. Weigh 0.6 g of Pregelatinized Modified Starch, and transfer to a 25-mL glass vial with a plastic cap. Add 9.4 g of water, cap, and shake vigorously to evenly disperse the starch. Add 10 g of 2% NaOH solution, cap, and shake vigorously for 1 minute to create a smooth mixture. Evaluate within 1 minute. The final solution is translucent to opaque with a fluid consistency. A yellow tint of the final solution is acceptable.
B: An aqueous dispersion of Pregelatinized Modified Starch is colored orange-red to deep blue by iodine TS.
pH 791 Wet 10.0 ± 0.1 g of Pregelatinized Modified Starch with 10 mL of alcohol, then dilute with water to 300 mL to obtain an aqueous dispersion. Stir continuously at a moderate rate for 5 minutes, and determine the pH to the nearest 0.1 unit: between 3.0 and 9.0.
Loss on drying 731 Dry it at 120 for 4 hours: it loses not more than 15% of its weight.
Residue on ignition 281: not more than 1.5%, a test specimen of 2.0 ± 0.1 g being used.
Oxidizing substances— To 5 g of Pregelatinized Modified Starch add 20 mL of a mixture of methanol and water (1:1), then add 1 mL of 6 N acetic acid, and stir until a homogeneous suspension is obtained. Add 0.5 mL of a freshly prepared saturated solution of potassium iodide, mix, and allow to stand for 5 minutes: no distinct blue, brown, or purple color is observed.
Limit of sulfur dioxide— Mix 20.0 ± 0.1 g of Pregelatinized Modified Starch with 100 mL of 95 percent alcohol, and stir for several minutes to completely wet the starch. Slowly add 100 mL of water, and stir until a smooth suspension is obtained. Allow the starch mixture to set undisturbed until most of the starch has settled, and filter the aqueous portion through paper (Whatman No. 1 or equivalent). To 100 mL of the clear filtrate add 100 mL of water, and mix. Add 3 mL of starch TS, and titrate with 0.01 N iodine VS to the first permanent blue or purple color. Not more than 1.7 mL is consumed: not more than 0.005% of sulfur dioxide is found.
Other requirements— It meets the requirements for Packaging and storage and in the tests for Microbial limits and Iron under Modified Starch.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Hong Wang, Ph.D.
(EM205) Excipient Monographs 2
USP32–NF27 Page 1356
Pharmacopeial Forum: Volume No. 29(4) Page 1133