Etidronate Disodium Tablets

» Etidronate Disodium Tablets contain not less than 90.0 percent and not more than 110.0 percent of the labeled amount of etidronate disodium (C2H6Na2O7P2).

Packaging and storage— Preserve in tight containers.

—

USP Etidronate Disodium RS

USP Etidronic Acid Monohydrate RS

C2H8O7P2·H2O 224.04

Identification, Infrared Absorption

197

— The spectra of trifluorovinyl chloride polymer and mineral oil dispersions, separately prepared from finely powdered Tablets recrystallized from water and dried at 105

for 1 hour, exhibit maxima in the regions of 4000 to 1350 cm

1 and 1350 to 450 cm

1, respectively, only at the same wavelengths as those of similar preparations of USP Etidronate Disodium RS.

Dissolution

711

—

Medium: water; 900 mL.

Apparatus 1: 100 rpm.

Time: 30 minutes.

Determine the amount of C2H6Na2O7P2 dissolved by employing the following method.

Mobile phase and Chromatographic system— Proceed as directed in the Assay under Etidronate Disodium.

Standard solution—

for products labeled to contain 200 mg of etidronate disodium— Transfer approximately 20 mg of USP Etidronic Acid Monohydrate RS to a 100-mL volumetric flask, dissolve in 50 mL of water, add 2.0 mL of 0.1 N sodium hydroxide, dilute with water to volume, and mix.

for products labeled to contain 400 mg of etidronate disodium— Transfer approximately 20 mg of USP Etidronic Acid Monohydrate RS to a 50-mL volumetric flask, dissolve in 25 mL of water, add 2.0 mL of 0.1 N sodium hydroxide, dilute with water to volume, and mix.

Test solution— Transfer a portion of the solution under test to an HPLC vial.

Procedure— Separately inject equal volumes (about 100 µL for products labeled to contain 200 mg of Etidronate Disodium, and about 50 µL for products labeled to contain 400 mg of Etidronate Disodium) of the Standard solution and the Test solution into the chromatograph, record the chromatograms, and measure the areas for the major peaks. Calculate the quantities of C2H6Na2O7P2 dissolved, employing the procedure set forth in the Assay, making any necessary volumetric adjustments.

Tolerances— Not less than 70% (Q) of the labeled amount of C2H6Na2O7P2 is dissolved in 30 minutes.

Uniformity of dosage units

905

: meet the requirements.

Assay—

Mobile phase, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Etidronate Disodium.

Assay preparation— Weigh and finely powder not fewer than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to 160 to 170 mg of Etidronate Disodium, to a 200-mL volumetric flask, and dilute with Mobile phase to volume. Agitate the solution for at least 5 minutes, and pass through a 0.45-µm nylon filter.

Procedure— Proceed as directed for Procedure in the Assay under Etidronate Disodium. Calculate the quantity, in mg, of etidronate disodium (C2H6Na2O7P2) in the portion of Tablets taken by the formula:

CSVU(250.00/224.05)(rU / rS)

in which 250.00 and 224.05 are the molecular weights of etidronate disodium and etidronic acid monohydrate, respectively; CS is the concentration, in mg per mL, of USP Etidronic Acid Monohydrate RS in the Standard preparation; VU is the volume, in mL, of the Assay preparation; and rU and rS are the peak responses obtained from the Assay preparation and the Standard preparation, respectively.

Auxiliary Information— Please check for your question in the FAQs before contacting USP.

Topic/Question	Contact	Expert Committee
Monograph	Elena Gonikberg, Ph.D. Principal Scientific Liaison 1-301-816-8251	(SM32010) Monographs - Small Molecules 3
Reference Standards	RS Technical Services 1-301-816-8129 rstech@usp.org
711	Margareth R.C. Marques, Ph.D. Senior Scientific Liaison 1-301-816-8106	(GCDF2010) General Chapters - Dosage Forms

USP35–NF30 Page 3139

Pharmacopeial Forum: Volume No. 30(5) Page 1619