Calcium Acetate
C4H6CaO4 158.17
Acetic acid, calcium salt;
Calcium acetate
[62-54-4].
(kal' see um as' e tate).
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C4H6CaO4 158.17
Acetic acid, calcium salt;
Calcium acetate
[62-54-4].DEFINITION
Calcium Acetate contains NLT 99.0% and NMT 100.5% of C4H6CaO4, calculated on the anhydrous basis.
IDENTIFICATION
• A. Identification Tests—General, Calcium 
191
and Acetate 191
191 and Acetate 191
Sample solution:
50 mg/mL
Acceptance criteria:
Meets the requirements
ASSAY
• Procedure
Sample:
300 mg
Analysis:
Dissolve the Sample in 150 mL of water containing 2 mL of 3 N hydrochloric acid. While stirring, preferably with a magnetic stirrer, add about 30 mL of 0.05 M edetate disodium VS from a 50-mL buret. Add 15 mL of 1 N sodium hydroxide and 300 mg of hydroxy naphthol blue, and continue the titration to a blue endpoint. Each mL of 0.05 M edetate disodium is equivalent to 7.909 mg of calcium acetate (C4H6CaO4).
Acceptance criteria:
99.0%–100.5% on the anhydrous basis
IMPURITIES
• Arsenic, Method I 211:
NMT 3 ppm
211:
NMT 3 ppm
• Chloride and Sulfate, Chloride 221:
A 1.0-g portion shows no more chloride than corresponds to 0.70 mL of 0.020 N hydrochloric acid (0.05%).
221:
A 1.0-g portion shows no more chloride than corresponds to 0.70 mL of 0.020 N hydrochloric acid (0.05%).
• Chloride and Sulfate, Sulfate 221:
A 0.25-g portion shows no more sulfate than corresponds to 0.15 mL of 0.020 N sulfuric acid (0.06%).
221:
A 0.25-g portion shows no more sulfate than corresponds to 0.15 mL of 0.020 N sulfuric acid (0.06%).
• Heavy Metals, Method I 231
231
Test preparation:
Dissolve 0.8 g of Calcium Acetate in 20 mL of water. Add 3.0 mL of glacial acetic acid, dilute with water to 25 mL, and adjust with glacial acetic acid to a pH of 3.8-4.0, measured with a pH meter.
Monitor preparation:
Prepare as directed for the Test preparation, 2.0 mL of Standard Lead Solution being added.
Acceptance criteria:
NMT 25 ppm
• Lead 251:
NMT 10 ppm
251:
NMT 10 ppm
• Limit of Aluminum
[Note—Use where it is labeled as intended for parenteral use or for use in hemodialysis or peritoneal dialysis. ]
Buffer:
Dissolve 50 g of ammonium acetate in 150 mL of water, adjust with glacial acetic acid to a pH of 6.0, and dilute with water to 250 mL.
Aluminum standard solution:
1.0 µg/mL of aluminum. Prepare as directed for Standard Preparations under Aluminum 206.
206.
Standard solution:
Prepare a solution containing 2.0 mL of Aluminum standard solution, 5 mL of Buffer, and 48 mL of water, and extract this solution with successive portions of 10, 10, and 5 mL of 0.5% 8-hydroxyquinoline in chloroform. Combine the chloroform extracts in a 50-mL volumetric flask. Dilute the combined extracts with chloroform to volume.
Sample solution:
Dissolve 1.0 g of Calcium Acetate in 50 mL of water, and add 5 mL of Buffer. Extract this solution with successive portions of 10, 10, and 5 mL of 0.5% 8-hydroxyquinoline in chloroform. Combine the chloroform extracts in a 50-mL volumetric flask. Dilute the combined extracts with chloroform to volume.
Blank solution:
Prepare a solution containing 50 mL of water and 5 mL of Buffer. Extract this solution with successive portions of 10, 10, and 5 mL of 0.5% 8-hydroxyquinoline in chloroform. Combine the chloroform extracts in a 50-mL volumetric flask. Dilute the combined extracts with chloroform to volume.
Instrumental conditions
Mode:
Fluorescence
Excitation wavelength:
392 nm
Emission wavelength:
518 nm
Analysis
Samples:
Standard solution, Sample solution, and Blank solution. Use the Blank solution to zero the instrument.
Acceptance criteria:
The fluorescence of the Sample solution is NMT that of the Standard solution (2 ppm).
• Limit of Barium
[Note—Use where it is labeled as intended for use in hemodialysis or peritoneal dialysis. ]
Barium chloride solution:
500 µg/mL of barium in water, from anhydrous barium chloride
Buffer:
Ammonium sulfate solution (1 in 10)
Standard solution:
To a tube add 1 g of ammonium acetate, 2 mL of 1 N hydrochloric acid, 3.0 mL of Barium chloride solution, and sufficient water to bring the volume to 40 mL.
Sample stock solution:
250 mg/mL of Calcium Acetate and 25 mg/mL of ammonium acetate in 1 N hydrochloric acid. The pH of this solution is 4.5–5.5. Filter and cover the solution.
Sample solutions:
To four separate tubes add 1.0, 1.5, 2.0, and 2.5 mL of Barium chloride solution. To each tube add a sufficient volume of the Sample stock solution to bring the volume to 40 mL.
Analysis:
To the Sample solutions and the Standard solution add, with brisk stirring, 3.0 mL of Buffer, and allow to stand for 20 min.
Acceptance criteria:
The Sample solutions containing 1.0 and 1.5 mL of Barium chloride solution remain clear or are only faintly turbid. The Sample solution containing 2.0 mL of Barium chloride solution is not more turbid than the Standard solution.
• Limit of Fluoride
[Note—Prepare and store all solutions in plastic containers. ]
Buffer:
294 mg/mL of sodium citrate dihydrate in water
Standard stock solution:
1.11 mg/mL of USP Sodium Fluoride RS, in water
Standard solution:
Combine 20.0 mL of Standard stock solution with 50.0 mL of Buffer, and dilute with water to 100.0 mL. Equivalent to 100 µg/mL of fluoride.
Sample solution:
Transfer 2.0 g of Calcium Acetate to a beaker containing a plastic-coated stirring bar. Add 20.0 mL of water and 2.0 mL of hydrochloric acid, and stir until dissolved. Add 50.0 mL of Buffer and sufficient water to make 100 mL.
Electrode system:
Use a fluoride-specific ion-indicating electrode and a silver–silver chloride reference electrode connected to a pH meter capable of measuring potentials with a minimum reproducibility of ±0.2 mV (see pH 791).
791).
Analysis
Samples:
Standard response line and Sample solution
Transfer 50.0 mL of Buffer and 2.0 mL of hydrochloric acid to a beaker, and add water to make 100 mL. Add a plastic-coated stirring bar, insert the electrodes into the solution, stir for 15 min, and read the potential, in mV. Continue stirring, and at 5-min intervals add 100, 100, 300, and 500 µL of Standard solution, reading the potential 5 min after each addition. Plot the logarithms of the cumulative fluoride ion concentrations (0.1, 0.2, 0.5, and 1.0 µg/mL) versus potential, in mV.
Rinse and dry the electrodes, insert them into the Sample solution, stir for 5 min, and read the potential, in mV. From the measured potential and the Standard response line determine the concentration, C, in µg/mL, of fluoride ion in the Sample solution.
Calculate the amount of fluoride (ppm) in the sample taken by multiplying C by 50.
Acceptance criteria:
50 ppm
• Limit of Magnesium
[Note—Use where it is labeled as intended for use in hemodialysis or peritoneal dialysis. The Standard solution and the Sample solutions may be modified, if necessary, to obtain solutions of suitable concentrations, adaptable to the linear or working range of the instrument. ]
Standard stock solution:
1000 µg/mL of magnesium in 1 N nitric acid, from magnesium oxide
Standard solution:
5.0 µg/mL of magnesium, from Standard stock solution
Sample solution:
2 mg/mL of Calcium Acetate
Linearity solution A:
Dilute 20.0 mL of Sample solution with water to 25.0 mL (0 µg/mL of magnesium).
Linearity solution B:
Dilute 2.0 mL of Standard solution and 20.0 mL of Sample solution with water to 25.0 mL (0.4 µg/mL of magnesium).
Linearity solution C:
Dilute 4.0 mL of Standard solution and 20.0 mL of Sample solution with water to 25.0 mL (0.8 µg/mL of magnesium).
Instrumental conditions
Mode:
Atomic absorption spectroscopy
Analytical wavelength:
285.2 nm
Flame:
Air–acetylene
Lamp:
Magnesium hollow-cathode
Blank:
Water
Analysis
Samples:
Linearity solutions A, B, and C
Plot the absorbances of the Linearity solutions versus their content (0, 0.4, and 0.8 µg/mL) of magnesium, draw the straight line best fitting the three points, and extrapolate the line until it intercepts the concentration axis. From the intercept determine the amount, in µg/mL, of magnesium in the Sample solution.
Calculate the percentage of magnesium in the sample by multiplying this value by 0.0625.
Acceptance criteria:
NMT 0.05%
• Limit of Nitrate
Sample solution:
100 mg/mL of Calcium Acetate in water
Analysis:
To 10 mL of the Sample solution add 5 mg of sodium chloride, 0.05 mL of indigo carmine TS, and, with stirring, 10 mL of nitrogen-free sulfuric acid.
Acceptance criteria:
The blue color persists for NLT 10 min.
• Limit of Potassium
[Note—Use where it is labeled as intended for use in hemodialysis or peritoneal dialysis. The Standard solution and the Sample solutions may be modified, if necessary, to obtain solutions of suitable concentrations, adaptable to the linear or working range of the instrument. ]
Standard stock solution:
23.84 mg/mL of potassium chloride, using potassium chloride previously dried at 105
for 2 h, equivalent to 12.5 mg/mL of potassium
for 2 h, equivalent to 12.5 mg/mL of potassium
Standard solution:
31.25 µg/mL of potassium, from Standard stock solution
Sample solution:
12.5 mg/mL of calcium acetate
Linearity solution A:
Dilute 20.0 mL of Sample solution with water to 25.0 mL (0 µg/mL of potassium).
Linearity solution B:
Dilute 2.0 mL of Standard solution and 20.0 mL of Sample solution with water to 25.0 mL (2.5 µg/mL of potassium).
Linearity solution C:
Dilute 4.0 mL of Standard solution and 20.0 mL of Sample solution with water to 25.0 mL (5.0 µg/mL of potassium).
Instrumental conditions
Mode:
Atomic absorption spectroscopy
Analytical wavelength:
766.7 nm
Lamp:
Potassium hollow-cathode
Flame:
Air–acetylene
Blank:
Water
Analysis
Samples:
Linearity solutions A, B, and C
Plot the absorbances of the Linearity solutions versus their content (0, 2.5, and 5.0 µg/mL) of potassium, draw the straight line best fitting the three points, and extrapolate the line until it intercepts the concentration axis. From the intercept determine the amount, in µg/mL, of potassium in the Sample solution.
Calculate the percentage of potassium in the sample by multiplying this value by 0.01.
Acceptance criteria:
NMT 0.05%
• Limit of Sodium
[Note—Use where it is labeled as intended for use in hemodialysis or peritoneal dialysis. The Standard solution and the Sample solutions may be modified, if necessary, to obtain solutions of suitable concentrations, adaptable to the linear or working range of the instrument. ]
Standard stock solution:
25.42 mg/mL of sodium chloride, using sodium chloride previously dried at 105 for 2 h, equivalent to 10.0 mg/mL of sodium
for 2 h, equivalent to 10.0 mg/mL of sodium
Standard solution:
250 µg/mL of sodium, from Standard stock solution
Sample solution:
10 mg/mL of Calcium Acetate
Linearity solution A:
Dilute 20.0 mL of Sample solution with water to 25.0 mL (0 µg/mL of sodium).
Linearity solution B:
Dilute 2.0 mL of Standard solution and 20.0 mL of Sample solution with water to 25.0 mL (20 µg/mL of sodium).
Linearity solution C:
Dilute 4.0 mL of Standard solution and 20.0 mL of Sample solution with water to 25.0 mL (40 µg/mL of sodium).
Instrumental conditions
Mode:
Atomic absorption spectroscopy
Analytical wavelength:
589.0 nm
Lamp:
Sodium hollow-cathode
Flame:
Air–acetylene
Blank:
Water
Analysis
Samples:
Linearity solutions A, B, and C
Plot the absorbances of the Linearity solutions versus their content (0, 20, and 40 µg/mL) of sodium, draw the straight line best fitting the three points, and extrapolate the line until it intercepts the concentration axis. From the intercept determine the amount, in µg/mL, of sodium in the Sample solution.
Calculate the percentage of sodium in the sample by multiplying this value by 0.0125.
Acceptance criteria:
NMT 0.5%
• Limit of Strontium
[Note—Use where it is labeled as intended for use in hemodialysis or peritoneal dialysis. The Standard solution and the Sample solutions may be modified, if necessary, to obtain solutions of suitable concentrations, adaptable to the linear or working range of the instrument. ]
Standard stock solution:
2.45 mg/mL of strontium acetate in water, equivalent to 1000 µg/mL of strontium
Standard solution:
50.0 µg/mL of strontium, from Standard stock solution
Sample solution:
20 mg/mL of Calcium Acetate
Linearity solution A:
Dilute 20.0 mL of Sample solution with water to 25.0 mL (0 µg/mL of strontium).
Linearity solution B:
Dilute 2.0 mL of Standard solution and 20.0 mL of Sample solution with water to 25.0 mL (4 µg/mL of strontium).
Linearity solution C:
Dilute 4.0 mL of Standard solution and 20.0 mL of Sample solution with water to 25.0 mL (8 µg/mL of strontium).
Instrumental conditions
Mode:
Atomic absorption spectroscopy
Analytical wavelength:
460.7 nm
Lamp:
Strontium hollow-cathode
Flame:
Nitrous oxide–acetylene
Blank:
Water
Analysis
Samples:
Linearity solutions A, B, and C
Plot the absorbances of the Linearity solutions versus their content (0, 4, and 8 µg/mL) of strontium, draw the straight line best fitting the three points, and extrapolate the line until it intercepts the concentration axis. From the intercept determine the amount, in µg/mL, of strontium in the Sample solution.
Calculate the percentage of strontium in the sample by multiplying this value by 0.00625.
Acceptance criteria:
NMT 0.05%
• Readily Oxidizable Substances
Sample solution:
20 mg/mL of Calcium Acetate in boiling water
Analysis:
Add a few glass beads to 100 mL of the Sample solution, 6 mL of 10 N sulfuric acid, and 0.3 mL of 1 N potassium permanganate. Mix, boil gently for 5 min, and allow the precipitate to settle.
Acceptance criteria:
The pink color in the supernatant is not completely discharged.
SPECIFIC TESTS
• Water Determination, Method I 921
921
Sample:
0.7 g
Analysis:
Proceed as directed in the chapter, adding 20.0 mL of glacial acetic acid to the titration vessel in addition to the methanol.
Acceptance criteria:
NMT 7.0%
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in tight containers.
• Labeling:
Where Calcium Acetate is intended for use in hemodialysis or peritoneal dialysis, it is so labeled.
• USP Reference Standards 11
11
USP Sodium Fluoride RS
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Domenick Vicchio, Ph.D.
Senior Scientific Liaison 1-301-998-6828 |
(SM42010) Monographs - Small Molecules 4 |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 2438
Pharmacopeial Forum: Volume No. 27(6) Page 3254