Sodium Acetate
C2H3NaO2·3H2O 136.08
C2H3NaO2 82.03
Acetic acid, sodium salt, trihydrate;
Sodium acetate trihydrate
[6131-90-4].
Anhydrous[127-09-3].
(soe' dee um as' e tate).
+'&img=../../images/v35300/cas-6131-90-4.gif&casNumber=6131-90-4&usp=35&nf=30&chemicalStructureImage=true&ID='+parent.myID,600,500);)
C2H3NaO2·3H2O 136.08
C2H3NaO2 82.03
Acetic acid, sodium salt, trihydrate;
Sodium acetate trihydrate
[6131-90-4].Anhydrous
[127-09-3].DEFINITION
Sodium Acetate contains three molecules of water of hydration, or is anhydrous. It contains NLT 99.0% and NMT 101.0% of C2H3NaO2, calculated on the dried basis.
IDENTIFICATION
• A. Identification Tests—General, Sodium 
191
:
Meets the requirements
191:
Meets the requirements
• B. Identification Tests—General, Acetate 191:
Meets the requirements
191:
Meets the requirements
Sample solution (for Lanthanum Nitrate test):
10 mg/mL of sodium acetate in water. Adjust with 0.1 N sodium hydroxide to a slightly alkaline pH.
ASSAY
• Procedure
Sample solution:
Equivalent to 200 mg of anhydrous sodium acetate in 25 mL of glacial acetic acid. [Note—Warm gently and mix to dissolve, if necessary. ]
Analysis:
Add 2 drops of p-naphtholbenzein TS to the Sample solution, and titrate with 0.1 N perchloric acid VS. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 8.203 mg of C2H3NaO2.
Acceptance criteria:
99.0%–101.0% on the dried basis
IMPURITIES
Inorganic Impurities
• Chloride and Sulfate, Chloride 221:
A portion equivalent to 1.0 g of anhydrous sodium acetate shows no more chloride than corresponds to 0.50 mL of 0.020 N hydrochloric acid (350 ppm).
221:
A portion equivalent to 1.0 g of anhydrous sodium acetate shows no more chloride than corresponds to 0.50 mL of 0.020 N hydrochloric acid (350 ppm).
• Chloride and Sulfate, Sulfate 221:
A portion equivalent to 10 g of anhydrous sodium acetate shows no more sulfate than corresponds to 0.50 mL of 0.020 N sulfuric acid (50 ppm).
221:
A portion equivalent to 10 g of anhydrous sodium acetate shows no more sulfate than corresponds to 0.50 mL of 0.020 N sulfuric acid (50 ppm).
• Calcium and Magnesium
Sample solution:
Equivalent to 10 mg/mL of anhydrous sodium acetate
Analysis:
To 20 mL of Sample solution add 2 mL each of 6 N ammonium hydroxide, ammonium oxalate TS, and dibasic sodium phosphate TS.
Acceptance criteria:
No turbidity is produced within 5 min.
• Potassium
Sample solution:
Equivalent to 600 mg/mL of anhydrous sodium acetate
Analysis:
To 5 mL of Sample solution add 1 N acetic acid dropwise until the solution is slightly acidic, and then add 5 drops of sodium cobaltinitrite TS.
Acceptance criteria:
No precipitate is formed.
• Aluminum 206:
Where it is labeled as intended for use in hemodialysis, proceed as directed in the chapter, using a portion equivalent to 10 g of sodium acetate trihydrate to prepare the Sample solution.
206:
Where it is labeled as intended for use in hemodialysis, proceed as directed in the chapter, using a portion equivalent to 10 g of sodium acetate trihydrate to prepare the Sample solution.
Acceptance criteria:
0.2 ppm
• Heavy Metals, Method I 231
231
Standard solution:
1 mL of Standard Lead Solution and 11 mL of water in a 50-mL color-comparison tube
Sample stock solution:
Dissolve the equivalent of 4.2 g of anhydrous sodium acetate in water to make 50 mL
Sample solution:
12 mL of Sample stock solution in a 50-mL color-comparison tube
Monitor solution:
11 mL of Sample stock solution and 1.0 mL of Standard Lead Solution in a 50-mL color-comparison tube
Analysis:
Proceed as directed in the chapter, omitting the dilution to 50 mL.
Acceptance criteria:
NMT 10 ppm
SPECIFIC TESTS
• pH 791:
7.5–9.2, in a solution equivalent to 30 mg/mL of anhydrous sodium acetate in carbon dioxide-free water
791:
7.5–9.2, in a solution equivalent to 30 mg/mL of anhydrous sodium acetate in carbon dioxide-free water
• Loss on Drying 731:
Dry a sample at 120
to constant weight: the hydrous form loses 38.0%–41.0% of its weight, and the anhydrous form loses NMT 1.0% of its weight.
731:
Dry a sample at 120 to constant weight: the hydrous form loses 38.0%–41.0% of its weight, and the anhydrous form loses NMT 1.0% of its weight.
• Insoluble Matter
Sample:
Equivalent to 20 g of anhydrous sodium acetate
Analysis:
Dissolve the Sample in 150 mL of water, heat to boiling, and digest in a covered beaker on a steam bath for 1 h. Filter through a tared filtering crucible, wash thoroughly, and dry at 105.
.
Acceptance criteria:
The weight of the residue is NMT 10 mg (0.05%).
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in tight containers.
• Labeling:
Label it to indicate whether it is the trihydrate or is anhydrous. Where Sodium Acetate is intended for use in hemodialysis, it is so labeled.
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 4644
Pharmacopeial Forum: Volume No. 36(2) Page 430