|
Citric Acid, Magnesium Oxide, and Sodium Carbonate Irrigation
» Citric Acid, Magnesium Oxide, and Sodium Carbonate Irrigation is a sterile solution of Citric Acid, Magnesium Oxide, and Sodium Carbonate in Water for Injection. It contains not less than 95.0 percent and not more than 105.0 percent of the labeled amounts of citric acid (C6H8O7·H2O), magnesium oxide (MgO), and sodium carbonate (Na2CO3).
Packaging and storage
Preserve in single-dose containers, preferably of Type I or Type II glass.
Identification
A:
It meets the requirements of the tests for Sodium
B:
To 10 mL of the Irrigation add 1 mL of mercuric sulfate TS, heat to boiling, and add a few drops of potassium permanganate TS: a white precipitate is formed.
Bacterial endotoxins
pH
Other requirements
It meets the requirements under Injections
Assay for citric acid
Mobile Phase, Standard Preparation 1, and Chromatographic System
Proceed as directed under Assay for Citric Acid/Citrate and Phosphate
Assay preparation
Transfer an accurately measured volume of Irrigation, equivalent to about 130 mg of monohydrate citric acid into a suitable volumetric flask, and proceed as directed for Assay Preparation for Citric Acid/Citrate Assay under Assay for Citric Acid/Citrate and Phosphate
Procedure
Proceed as directed for Procedure under
0.001(210.14 / 189.10)CS(D/V)(rU / rS)
in which 210.14 is the molecular weight of citric acid monohydrate; 189.10 is the molecular weight of citrate (C6H5O7); CS is the concentration, in µg per mL, of citrate in Standard Preparation 1; D is the dilution factor; V is the volume, in mL, of Irrigation used to prepare the Assay preparation; and rU and rS are the citrate peak areas obtained from the Assay preparation and Standard Preparation 1, respectively.
Assay for magnesium oxide
Transfer an accurately measured volume of Irrigation, equivalent to about 40 mg of magnesium oxide, to a beaker containing 130 mL of water heated to 75 ± 5
Assay for sodium carbonate
Sodium chloride stock solution
Transfer 475 mg of sodium chloride, previously dried at 105
Internal standard solution
Transfer 636 mg of lithium chloride to a 1000-mL volumetric flask, dissolve in and dilute with water to volume, and mix.
Standard preparation
Quantitatively prepare a mixture of Internal standard solution and Sodium chloride stock solution (99:1).
Assay preparation
Dilute an accurately measured volume of Irrigation quantitatively with water to obtain a stock solution containing about 4.4 mg of sodium carbonate per mL. Quantitatively prepare a mixture of Internal standard solution and this stock solution (99:1).
Procedure
Concomitantly determine the emittances of the Standard preparation and the Assay preparation at 591 nm and 671 nm with a suitable flame photometer, adjusting the instrument to zero emittance with Internal standard solution. Calculate the quantity, in mg, of Na2CO3 in each mL of the Irrigation taken by the formula:
(105.99/116.88)(C)(L/D)(RU,591 / RU,671)(RS,671 / RS,591)
in which 105.99 is the molecular weight of sodium carbonate; 116.88 is two times the molecular weight of sodium chloride; C is the concentration, in mg per mL, of sodium chloride in the Sodium chloride stock solution; L is the labeled quantity, in mg per mL, of sodium carbonate in the Irrigation; D is the concentration, in mg per mL, of sodium carbonate in the stock solution used to prepare the Assay preparation, on the basis of the labeled quantity in each mL, and the extent of dilution; RU,591 and RU,671 are the emittance readings obtained from the Assay preparation at the wavelengths indicated by the subscripts; and RS,671 and RS,591 are the emittance readings obtained from the Standard preparation at the wavelengths indicated by the subscripts.
Auxiliary Information
Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 2689
Pharmacopeial Forum: Volume No. 31(2) Page 394
|