Calcium Levulinate
(kal' see um lev'' ue lin' ate).

C10H14CaO6·2H2O 306.32

C10H14CaO6 270.30
Pentanoic acid, 4-oxo-, calcium salt (2:1), dihydrate;
Calcium levulinate (1:2) dihydrate     [5743-49-7].
Anhydrous     [591-64-0].
DEFINITION
Calcium Levulinate contains NLT 97.5% and NMT 100.5% of calcium levulinate (C10H14CaO6), calculated on the dried basis.
IDENTIFICATION
A 100 mg/mL solution meets the requirements.
•  B.
Sample solution:  0.5 g in 5 mL of water
Analysis:  To the Sample solution add 5 mL of 1 N sodium hydroxide, and filter. To the filtrate add 5 mL of iodine TS.
Acceptance criteria:  A precipitate of iodoform is produced.
ASSAY
•  Procedure
Sample:  600 mg of Calcium Levulinate
Blank:  150 mL of water containing 2 mL of 3 N hydrochloric acid
Titrimetric system
Mode:  Direct titration
Titrant:  0.05 M edetate disodium VS
Endpoint detection:  Visual
Analysis:  Dissolve the Sample in 150 mL of water containing 2 mL of 3 N hydrochloric acid. While stirring with a magnetic stirrer, add 30 mL of Titrant from the titration buret. Add 15 mL of 1 N sodium hydroxide and 300 mg of hydroxy naphthol blue, and continue the titration to a blue endpoint. Perform the Blank determination.
Calculate the percentage of calcium levulinate (C10H14CaO6) in the Sample taken:
Result = {[(VS VB) × M × F]/W} × 100
 VS = = Titrant volume consumed by the Sample (mL) VB = = Titrant volume consumed by the Blank (mL) M = = Titrant molarity (mM/mL) F = = equivalency factor, 270.3 mg/mM W = = Sample weight (mg)
Acceptance criteria:  97.5%–100.5% on the dried basis
IMPURITIES
Standard:   1.0 mL of 0.020 N hydrochloric acid
Sample:  1.0 g
Acceptance criteria:  NMT 0.07%
Standard:   1.0 mL of 0.020 N sulfuric acid
Sample:  2.0 g
Acceptance criteria:  NMT 0.05%
NMT 20 ppm
•  Reducing Sugars
Sample:  0.50 g
Analysis:  Dissolve the Sample in 10 mL of water, add 2 mL of 3 N hydrochloric acid, boil for about 2 min, and cool. Add 5 mL of sodium carbonate TS, allow to stand for 5 min, dilute with water to 20 mL, and filter. Add 5 mL of the clear filtrate to 2 mL of alkaline cupric tartrate TS, and boil for 1 min.
Acceptance criteria:  No red precipitate is formed immediately.
SPECIFIC TESTS
119–125
Sample solution:  100 mg/mL
Acceptance criteria:  7.0–8.5
Dry a sample at a pressure not exceeding 5 mm of mercury at 60 for 5 h: it loses 10.5%–12.0% of its weight.