Potassium Gluconate and Potassium Chloride Oral Solution
» Potassium Gluconate and Potassium Chloride Oral Solution is a solution of Potassium Gluconate and Potassium Chloride in a suitable aqueous medium. It contains not less than 90.0 percent and not more than 110.0 percent of the labeled amounts of potassium (K) and chloride (Cl).
Packaging and storage Preserve in tight containers.
Labeling Label it to state the potassium and chloride contents in terms of milliequivalents of each in a given volume of Oral Solution.
A: To 2 mL of a dilution of Oral Solution (1 in 40) add 5 mL of sodium cobaltinitrite TS: a yellow precipitate is formed immediately (presence of potassium).
B: Evaporate 5 mL on a steam bath to dryness: a mineral oil dispersion of the residue so obtained exhibits an IR absorption maximum in the spectral region between 6.2 and 6.25 µm (carboxylic acid salt).
C: It responds to the tests for Chloride 191.
Assay for potassium
Potassium stock solution Dissolve in water 0.9535 g of potassium chloride, previously dried at 105 for 2 hours. Transfer to a 500-mL volumetric flask, dilute with water to volume, and mix. This solution contains 1000 µg of potassium per mL.
Standard preparations To separate 200-mL volumetric flasks transfer 19.0 mL and 25.0 mL, respectively, of Potassium stock solution, dilute with water to volume, and mix. The Standard preparations contain 95.0 µg and 125.0 µg of potassium per mL, respectively.
Assay preparation Transfer an accurately measured volume of Oral Solution, equivalent to about 782 mg (20 mEq) of potassium, to a 100-mL volumetric flask, dilute with water to volume, and mix. Transfer 7.0 mL of the resulting solution to a 500-mL volumetric flask, dilute with water to volume, and mix.
Procedure Concomitantly determine the absorbances of the Standard preparations and the Assay preparation at the resonance line of 766.5 nm, with a suitable atomic absorption spectrophotometer (see Spectrophotometry and Light-scattering 851) equipped with a potassium hollow-cathode lamp and an airacetylene flame, using water as the blank. Plot the absorbances of the Standard preparations versus concentration, in µg per mL, of potassium. From the graph so obtained, determine the concentration, C, in µg per mL, of potassium in the Assay preparation. Calculate the quantity, in mg, of potassium in each mL of the Oral Solution taken by the formula:
(50 / 7)(C / V)in which V is the volume, in mL, of Oral Solution taken. Each mg of potassium is equivalent to 0.02558 mEq.
Assay for chloride
Ionic strength adjusting solution Use 5 M sodium nitrate.
Procedure Transfer an accurately measured volume of Oral Solution, equivalent to about 100 mg (2.8 mEq) of chloride, to a suitable beaker. Add 2.0 mL of Ionic strength adjusting solution and water to make about 100 mL, and titrate with 0.1 N silver nitrate VS, determining the endpoint potentiometrically, using a silver-sulfide specific ion-selective electrode and a double-junction reference electrode containing potassium nitrate solution (1 in 10). Perform a blank determination, and make any necessary correction. Each mL of 0.1 N silver nitrate is equivalent to 3.545 mg of chloride (Cl). Each mg of chloride is equivalent to 0.0282 mEq of Cl.