Potassium Chloride Oral Solution
DEFINITION
Potassium Chloride Oral Solution contains NLT 95.0% and NMT 105.0% of the labeled amount of potassium chloride (KCl). It may contain alcohol.
IDENTIFICATION
• A. Identification Tests—General, Potassium 
191
191
Sample solution:
Carefully evaporate 5 mL to dryness, and ignite the residue at dull-red heat to remove all organic matter. Cool, dissolve the residue in 10 mL of water, and filter.
Acceptance criteria:
Meets the requirements
• B. Identification Tests—General, Chloride 191
191
Sample solution:
Carefully evaporate 5 mL to dryness, and ignite the residue at dull-red heat to remove all organic matter. Cool, dissolve the residue in 10 mL of water, and filter.
Acceptance criteria:
Meets the requirements
ASSAY
• Procedure
Standard stock solution:
19.07 µg/mL of potassium chloride, previously dried at 105
for 2 h, in water. This solution contains 10 µg/mL of potassium.
for 2 h, in water. This solution contains 10 µg/mL of potassium.
Standard solutions:
To separate 100-mL volumetric flasks transfer 10.0, 15.0, and 20.0 mL, respectively, of Standard stock solution. To each flask add 2.0 mL of sodium chloride solution (200 mg/mL) and 1.0 mL of hydrochloric acid, and dilute with water to volume. The Standard solutions contain, respectively, 1.0, 1.5, and 2.0 µg/mL of potassium.
Sample stock solution:
Transfer a volume of Oral Solution, equivalent to 600 mg of potassium chloride, to a 500-mL volumetric flask, and dilute with water to volume. Transfer 5.0 mL of the solution to a 100-mL volumetric flask, and dilute with water to volume.
Sample solution:
Transfer 5.0 mL of Sample stock solution to a 100-mL volumetric flask, add 2.0 mL of sodium chloride solution (200 mg/mL) and 1.0 mL of hydrochloric acid, and dilute with water to volume.
Instrumental conditions
Mode:
Atomic absorption spectrophotometry
Analytical wavelength:
Potassium emission line at 766.5 nm
Lamp:
Potassium hollow-cathode
Flame:
Air–acetylene
Blank:
Water
Analysis
Samples:
Standard solutions, Sample solution, and Blank
Plot the absorbance of the Standard solutions versus the concentration of potassium, in µg/mL, and draw the straight line best fitting the three plotted points. From the graph so obtained, determine the concentration of potassium in the Sample solution (µg/mL).
Calculate the percentage of the labeled amount of potassium chloride (KCI) in the portion of Oral Solution taken:
Result = (C/CU) × (Mr/Ar) × 100
| C | = | = concentration of potassium in the Sample solution as determined in this test (µg/mL) |
| CU | = | = nominal concentration of potassium chloride in the Sample solution (µg/mL) |
| Mr | = | = molecular weight of potassium chloride, 74.55 |
| Ar | = | = atomic weight of potassium, 39.10 |
Acceptance criteria:
95.0%–105.0%
SPECIFIC TESTS
• Alcohol Content, Method II 611 (if present):
NLT 90.0% and NMT 115.0% of the labeled amount, the labeled amount being NMT 7.5% of C2H5OH, acetone being used as the internal standard
611 (if present):
NLT 90.0% and NMT 115.0% of the labeled amount, the labeled amount being NMT 7.5% of C2H5OH, acetone being used as the internal standard
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in tight containers.
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Mary S. Waddell
Scientific Liaison 1-301-816-8124 |
(SM42010) Monographs - Small Molecules 4 |
USP35–NF30 Page 4361