Ethyl Vanillin
C9H10O3 166.17
Benzaldehyde, 3-ethoxy-4-hydroxy-;
3-Ethoxy-4-hydroxybenzaldehyde
[121-32-4].
(eth' il van' il in).
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C9H10O3 166.17
Benzaldehyde, 3-ethoxy-4-hydroxy-;
3-Ethoxy-4-hydroxybenzaldehyde
[121-32-4].DEFINITION
Ethyl Vanillin, dried over phosphorus pentoxide for 4 h, contains NLT 98.0% and NMT 101.0% of C9H10O3.
IDENTIFICATION
• B. Ultraviolet Absorption 
197U
197U
Sample solution:
8 µg/mL in methanol
Acceptance criteria:
Meets the requirements
ASSAY
• Procedure
Sample:
300 mg of Ethyl Vanillin (previously dried)
Titrimetric system
(See Titrimetry 541.)
541.)
Mode:
Direct titration
Titrant:
0.1 N sodium methoxide VS
Blank:
50 mL of dimethylformamide, accurately measured
Endpoint detection:
Visual
Analysis:
Transfer the Sample solution to a 125-mL conical flask, and dissolve in 50 mL of dimethylformamide. Add thymol blue TS and titrate, using a magnetic stirrer and taking precautions against the absorption of atmospheric carbon dioxide. Perform a blank determination. Calculate the percentage of ethyl vanillin (C9H10O3) in the Sample taken:
Result = {[(VS 
VB) × N × F]/W} × 100
VB) × N × F]/W} × 100| VS | = | = Titrant volume consumed by the Sample (mL) |
| VB | = | = Titrant volume consumed by the Blank (mL) |
| N | = | = actual normality of the Titrant (mEq/mL) |
| F | = | = equivalency factor, 166.2 mg/mEq |
| W | = | = Sample weight (mg) |
Acceptance criteria:
98.0%–101.0% on the previously dried basis
IMPURITIES
• Residue on Ignition 281:
NMT 0.1%
281:
NMT 0.1%
SPECIFIC TESTS
• Melting Range or Temperature 741:
76
–78
741:
76–78
• Loss on Drying 731:
Dry a sample over phosphorus pentoxide for 4 h: it loses NMT 1.0% of its weight.
731:
Dry a sample over phosphorus pentoxide for 4 h: it loses NMT 1.0% of its weight.
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in tight, light-resistant containers.
• USP Reference Standards 11
11
USP Ethyl Vanillin RS 
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Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Robert H. Lafaver, M.S.
Scientific Liaison 1-301-816-8335 |
(EXC2010) Monographs - Excipients |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 1794