Lysine Hydrochloride Tablets
» Lysine Hydrochloride Tablets contain not less than 90.0 percent and not more than 120.0 percent of the labeled amount of C6H14N2O2·HCl, as l-lysine hydrochloride.
Packaging and storage— Preserve in well-closed containers, and store at controlled room temperature.
USP Reference standards 11 USP l-Lysine Hydrochloride RS.
Thin-layer chromatographic identification test 201
Test solution— Powder and transfer a portion of Tablets equivalent to about 40 mg of lysine hydrochloride to a 100-mL volumetric flask. Dilute with water to volume, mix, and filter. Use the filtrate.
Standard solution— Dissolve an accurately weighed quantity of USP l-Lysine Hydrochloride RS in water to obtain a solution having a known concentration of about 0.4 mg per mL.
Developing solvent system— Prepare a mixture of isopropyl alcohol and ammonium hydroxide (70:30).
Spray reagent— Dissolve 0.2 g of ninhydrin in 100 mL of a mixture of butyl alcohol and 2 N acetic acid (95:5).
Procedure— Proceed as directed in the chapter. Dry the plate between 100 and 105 until the ammonia disappears completely. Spray with Spray reagent, and heat between 100 and 105 for about 15 minutes. Examine the plate under white light.
Disintegration and dissolution of dietary supplements 2040: meet the requirements for Disintegration only, 20 minutes.
Assay— Weigh and finely powder not fewer than 20 Tablets. Transfer about 75 mg of lysine hydrochloride, accurately weighed, to a 125-mL flask, and dissolve in 5 mL of mercuric acetate TS with gentle heating. Cool, then add 50 mL of glacial acetic acid and 3 drops of crystal violet TS, and titrate with 0.1 N perchloric acid VS, determining the endpoint potentiometrically. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 9.133 mg of l-lysine hydrochloride (C6H14N2O2·HCl).
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Monograph Curtis Phinney

(DSN05) Dietary Supplements - Non-Botanicals
Reference Standards Lili Wang, Technical Services Scientist
USP32–NF27 Page 1050
Pharmacopeial Forum: Volume No. 30(5) Page 1665