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Sodium Chloride
NaCl 58.44

Sodium Chloride
Sodium Chloride [7647-14-5].
»Sodium Chloride contains not less than 99.0percent and not more than 100.5percent of NaCl,calculated on the dried basis.
Packaging and storage— Preserve in well-closed containters.
Labeling— Where Sodium Chloride is intended for use in the manufacture of injectable dosage forms,peritoneal dialysis solutions,hemodialysis solutions,or hemofiltration solutions,it is so labeled.Where Sodium Chloride must be subjected to further processing during the preparation of injectable dosage forms to ensure acceptable levels of Bacterial endotoxins,it is so labeled.Where Sodium Chloride is sterile,it is so labeled.
Appearance of solution— Dissolve 20.0g of Sodium Chloride in carbon dioxide-free water,and dilute with the same solvent to 100.0mL.This solution is clear and colorless.
Identification— It responds to the tests for Sodium á191ñand forChloride.
Chloride— Dissolve about 3mg of Sodium Chloride in 2mLof water.Acidify with diluted nitric acid and add 0.4mLof silver nitrate TS.Shake,and allow to stand.Acurdled,white precipitate is formed.Centrifuge,wash the precipitate with three 1-mLportions of water,and discard the washings.Carry out this operation rapidly in subdued light,disregarding the fact that the supernatant may not become perfectly clear.Suspend the precipitate in 2mLof water and add 1.5mLof 10Nammonium hydroxide.The precipitate dissolves easily with the possible exception of a few large particles,which dissolve more slowly.
Bacterial endotoxins á85ñ— The level of Bacterial endotoxinsare such that the requirement under the relevant dosage form monograph(s)in which Sodium Chloride is used can be met.Where the label states that Sodium Chloride must be subjected to further processing during the preparation of injectable dosage forms,the level of Bacterial endotoxinsare such that the requirement under the relevant dosage form monograph(s)in which Sodium Chloride is used can be met.
Sterility á71ñ— Where the label states that Sodium Chloride is sterile,it meets the requirements for Sterility under the relevant dosage form monograph(s)in which Sodium Chloride is used.
Acidity or alkalinity— To 20mLof the solution prepared for the test forAppearance of solution,add 0.1mLof bromothymol blue TS:not more than 0.5mLof 0.01Nhydrochloric acid or 0.01Nsodium hydroxide is required to change the color of this solution.
Loss on drying á731ñ— Dry the test material at 105ºfor 2hours:it loses not more than 0.5%of its weight,determined on a 1.000g sample.
Limit of bromides— To 0.5mLof the solution prepared for the test forAppearance of solution,add 4.0mLof water,2.0mLof pH4.7phenol red TS,and 1.0mLof chloramine Tsolution (0.1mg per mL),and mix immediately.After 2minutes,add 0.15mLof 0.1Nsodium thiosulfate,mix,dilute with water to 10.0mL,and mix.The absorbance of this solution measured at 590nm,using water as the comparison liquid,is not greater than that of aStandard solution,concomitantly prepared,using 5.0mLof a solution containing 3.0mg of potassium bromide per Land proceeding as above,starting with the addition of 2.0mLof pH4.7phenol red TS(0.010%).
Limit of phosphates—
Phosphate stock standard solution— Dissolve an accurately weighed quantity of monobasic potassium phosphate in water to obtain a solution having a concentration of about 0.716mg per mL.
Phosphate standard solution— Dilute 1mLof the Stock standard solutionwith water to 100mL.Prepare this solution fresh.
Standard solution— Dilute 2mLof the Phosphate standard solutionwith water to 100mL.
Test solution— Dilute 2mLof the solution prepared in the test for Appearance of solutionwith water to 100mL.
Procedure— To the Standard solutionand the Test solution,add 4mLof sulfomolybdic acid TS,and add 0.1mLof a mixture of 1mLof stronger acid stannous chloride TSand 10mLof 2Nhydrochloric acid.After 10minutes,compare the colors of 20mLof each solution:any color in the Test solutionis not more intense than that in the Standard solution(0.0025%).
Limit of potassium(where it is labeled as intended for use in the manufacture of injectable dosage forms,peritoneal dialysis solutions,hemodialysis solutions,or hemofiltration solutions)—
Test solution— Transfer 1.00g of Sodium Chloride to a 100-mLvolumetric flask,add water and swirl to dissolve,dilute with water to volume,and mix.
Standard solution— [NOTE—TheStandard solution and the Test solution may be modified,if necessary,to obtain solutions of suitable concentrations adaptable to the linear or working range of the instrument.]Dissolve 1.144g of potassium chloride,previously dried at 105ºfor 3hours,in water,dilute with water to 1000mL,and mix.This solution contains the equivalent of 600µg of potassium per mL.Dilute as required to obtain not fewer than three solutions at concentrations that span the expected value in theTest solution.
Procedure— Using atomic absorption spectrophotometry (seeSpectrophotometry and Light-Scattering á851ñ),measure,at least three times,the emission intensity of theTest solution and theStandard solution using an air–acetylene flame and a wavelength of 766.5nm.Prepare a calibration curve from the mean of the readings obtained with theStandard solution,and determine the concentration of potassium in theTest solution.The limit is 0.05%.
Iodides— Moisten 5g of Sodium Chloride by the dropwise addition of a freshly prepared mixture of 0.15mLof sodium nitrite solution (1in 10),2mLof 1Nsulfuric acid,25mLof iodide-free starch TS,and 25mLof water.After 5minutes,examine the substance in natural light.No blue color is observed.
Aluminum(where it is labeled as intended for use in the manufacture of peritoneal dialysis solutions,hemodialysis solutions,or hemofiltration solutions)—
Standard aluminum solution— To 352mg of aluminum potassium sulfate in a 100-mLvolumetric flask,add a few mLof water,swirl to dissolve,add 20mLof diluted sulfuric acid,dilute with water to volume,and mix.Immediately before use,transfer 1.0mLof this solution to a 100-mLvolumetric flask,dilute with water to volume,and mix.
pH6.0Acetate buffer— Dissolve 50g of ammonium acetate in 150mLof water,adjust with glacial acetic acid to a pHof 6.0,dilute with water to 250mL,and mix.
Test solution— Dissolve 20.0g of Sodium Chloride in 100mLof water,and add 10mLofpH6.0Acetate buffer.Extract this solution with successive portions of 20,20,and 10mLof a 0.5%solution of 8-hydroxyquinoline in chloroform,combining the chloroform extracts in a 50-mLvolumetric flask.Dilute the combined extracts with chloroform to volume,and mix.
Standard solution— Prepare a mixture of 2.0mLofStandard aluminum solution,10mLof pH6.0Acetate buffer,and 98mLof water.Extract this mixture as described for theTest solution,dilute the combined extracts with chloroform to volume,and mix.
Blank solution— Prepare a mixture of 10mLofpH6.0Acetate buffer and 100mLof water.Extract this mixture as described for theTest solution,dilute the combined extracts with chloroform to volume,and mix.
Procedure— Determine the fluorescence intensities of theTest solution and theStandard solution in a fluorometer set at an excitation wavelength of 392nm and an emission wavelength of 518nm,using theBlank solution to set the instrument to zero.The fluorescence of theTest solution does not exceed that of theStandard solution (0.2µg per g).
Magnesium and alkaline-earth metals— To 200mLof water add 0.1g of hydroxylamine hydrochloride,10mLof pH10.0ammonia–ammonium chloride buffer (prepared by dissolving 5.4g of ammonium chloride in 20mLof water,adding 20mLof ammonium hydroxide and diluting to 100mL),1mLof 0.1Mzinc sulfate,and about 0.2g of eriochrome black Ttrituration.Heat to about 40º.Titrate this solution with 0.01Medetate disodium VSuntil the violet color changes to deep blue.To this solution add 10.0g of Sodium Chloride dissolved in 100mLof water.If the color changes to violet,titrate the solution with 0.01Medetate disodium VSto a deep blue endpoint.The volume of 0.01Medetate disodium consumed in the second titration does not exceed 2.5mL(0.01%,calculated as Ca).
Iron—
Test solution— Use a 10-mLportion of the solution prepared for the test forAppearance of solution.
Standard solution— Immediately before use,diluteStandard Iron Solution (seeIron á241ñ)1to 10with water.This solution contains the equivalent of 1µg of iron per mL.Combine 4mLof this solution and 6mLof water.
Procedure— To each of the solutions,add 2mLof a 200g per Lsolution of citric acid and 0.1mLof thioglycolic acid.Mix,make alkaline with stronger ammonia water,and dilute with water to 20mL.After 5minutes,any pink color in the Test solution is not more intense than that from theStandard solution.The limit is 2µg per g.
Barium— To 5mLof the solution prepared for the test forAppearance of solution,add 2mLof 2Nsulfuric acid and 5mLof water.To another 5mLof the solution prepared for the test forAppearance of solution,add 7mLof water.The solutions are equally clear after standing for 2hours.
Ferrocyanides— Dissolve 2.0g in 6mLof water.Add 0.5mLof a mixture of 5mLof ferric ammonium sulfate solution (1g in 100mLof 0.1Nsulfuric acid)and 95mLof ferrous sulfate solution (1in 100):no blue color develops in 10minutes.
Sulfate—
Standard sulfate solution A— To 181mg of potassium sulfate in a 100-mLvolumetric flask,add a few mLof 30%alcohol,swirl to dissolve,dilute with 30%alcohol to volume,and mix.Immediately before use,transfer 10.0mLof this solution to a 1000-mLvolumetric flask,dilute with 30%alcohol to volume,and mix.This solution contains 10µg of sulfate per mL.
Standard sulfate solution B— To 181mg of potassium sulfate in a 100-mLvolumetric flask,add a few mLof water,swirl to dissolve,dilute with water to volume,and mix.Immediately before use,transfer 10.0mLof this solution to a 1000-mLvolumetric flask,dilute with water to volume,and mix.This solution contains 10µg of sulfate per mL.
Sodium chloride solution— Dissolve 2.5g of Sodium Chloride in 50mLof water.
Procedure— To 1.5mLofStandard sulfate solution Aadd 1mLof a barium chloride solution (1in 4),shake,and allow to stand for 1minute.To 2.5mLof the resulting suspension,add 15mLof the Sodium chloride solutionand 0.5mLof 5Nacetic acid,and mix (Test solution).Prepare theStandard solution in the same manner,except use 15mLofStandard sulfate solution Binstead of the Sodium chloride solution:any turbidity produced in theTest solution after 5minutes standing is not greater than that produced in theStandard solution (0.020%).
Nitrites— To 10mLof the solution prepared in the test forAppearance of solution,add 10mLof water,and measure the absorbance of the solution in a 1-cm cell at 354nm.The absorbance is not greater than 0.01.
Assay— Dissolve 50mg of Sodium Chloride,accurately weighed,in water and dilute with water to 50mL.Titrate with 0.1Nsilver nitrate VS,determining the endpoint potentiometrically (see Titrimetry á541ñ).Each mLof 0.1Nsilver nitrate is equivalent to 5.844mg of NaCl.USP28
Auxiliary Information— Staff Liaison:Karen A Russo,Ph.D.,Scientist
Expert Committee:(PA1)Pharmaceutical Analysis 1
USP28–NF23Page 1779
Pharmacopeial Forum:Volume No.30(2)Page 685
Phone Number:1-301-816-8379