» Belladonna Tincture yields, from each 100 mL, not less than 27 mg and not more than 33 mg of the alkaloids of belladonna leaf.
Prepare a tincture by Process P as modified for assayed Tinctures (see Pharmaceutical Dosage Forms 1151), using a mixture of 3 volumes of alcohol and 1 volume of water as the menstruum. Finally adjust the Tincture to contain, in each 100 mL, 30 mg of the alkaloids of belladonna leaf.
Packaging and storage Preserve in tight, light-resistant containers, and avoid exposure to direct sunlight and to excessive heat.
USP Reference standards 11
USP Atropine Sulfate RS.
USP Homatropine Hydrobromide RS.
USP Scopolamine Hydrobromide RS.
Alcohol content, Method II 611: between 65.0% and 70.0% of C2H5OH, determined by the gas-liquid chromatographic procedure, acetone being used as the internal standard.
pH 9.5 Phosphate buffer , Internal standard solution, Standard preparation, Extraction blank, Standard curve, Chromatographic system, and System suitabilityProceed as directed in the Assay under Belladonna Extract.
Assay preparation Proceed with Tincture as directed in the Assay under Belladonna Leaf, but pipet 2 mL of Tincture (in place of 10 mL of this solution) into a 60-mL separator containing 10 mL of dilute sulfuric acid (1 in 350).
Procedure Proceed as directed in the Assay under Belladonna Leaf. Record from the Standard curve the quantities, in mg, of atropine and scopolamine in the specimen. Add the quantity, in mg, of atropine and scopolamine, and multiply by 50 to obtain the weight, in mg, of alkaloids per 100 mL.
Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP32NF27 Page 1633