Potassium Acetate Injection
»Potassium Acetate Injection is a sterile solution of Potassium Acetate in Water for Injection.It contains not less than 95.0percent and not more than 105.0percent of the labeled amount of C2H3KO2.
Packaging and storage— Preserve in single-dose or in multiple-dose containers,preferably of Type Ior Type IIglass.
Labeling— The label states the potassium acetate content in terms of weight and of milliequivalents in a given volume.Label the Injection to indicate that it is to be diluted to appropriate strength with water or other suitable fluid prior to administration.The label states also the total osmolar concentration in mOsmol per liter.Where the contents are less than 100mL,or where the label states that the Injection is not for direct injection but is to be diluted before use,the label alternatively may state the total osmolar concentration in mOsmol per mL.
Identification— It responds to the tests for Potassium á191ñand for Acetate á191ñ.
Bacterial endotoxins á85ñ— It contains not more than 8.80USP Endotoxin Units per mEq.
pHá791ñ: between 5.5and 8.0,when diluted with water to 1.0%of potassium acetate.
Particulate matter á788ñ: meets the requirements under small-volume injections.
Other requirements— It meets the requirements under Injections á1ñ.
Assay—
Potassium stock solution— Dissolve 190.7mg of potassium chloride,previously dried at 105for 2hours,in water.Transfer to a 1000-mLvolumetric flask,dilute with water to volume,and mix.Transfer 100.0mLof this solution to a 1000-mLvolumetric flask,dilute with water to volume,and mix.This solution contains 10µg of potassium (equivalent to 19.07µg of potassium chloride)per mL.
Standard preparations— To separate 100-mLvolumetric flasks transfer 10.0,15.0,and 20.0mL,respectively,of Potassium stock solution.To each flask add 2.0mLof sodium chloride solution (1in 5)and 1.0mLof hydrochloric acid,dilute with water to volume,and mix.The Standard preparationscontain,respectively,1.0,1.5,and 2.0µg of potassium per mL.
Assay preparation— Transfer an accurately measured volume of Injection,equivalent to about 2g of potassium acetate,to a 500-mLvolumetric flask,dilute with water to volume,and mix.Transfer 5.0mLof the solution to a 250-mLvolumetric flask,dilute with water to volume,and mix.Transfer 5.0mLof the resulting solution to a 100-mLvolumetric flask,add 2.0mLof sodium chloride solution (1in 5)and 1.0mLof hydrochloric acid,dilute with water to volume,and mix.
Procedure— Concomitantly determine the absorbances of the Standard preparationsand the Assay preparationat the potassium emission line of 766.5nm,with a suitable atomic absorption spectrophotometer (see Spectrophotometry and Light-scattering á851ñ)equipped with a potassium hollow-cathode lamp and an air–acetylene flame,using water as the blank.Plot the absorbance of the Standard preparationversus concentration,in µg per mL,of potassium,and draw the straight line best fitting the three plotted points.From the graph so obtained,determine the concentration,in µg per mL,of potassium in the Assay preparation.Calculate the quantity,in mg,of C2H3KO2in the portion of Injection taken by the formula:
500C(2.510),
in which Cis the concentration,in µg per mL,of potassium in the Assay preparation,and 2.510is the ratio of the molecular weight of potassium acetate to the atomic weight of potassium.
Auxiliary Information— Staff Liaison:Lawrence Evans,III,Ph.D.,Scientist
Expert Committee:(PA6)Pharmaceutical Analysis 6
USP28–NF23Page 1580
Phone Number:1-301-816-8389