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C8H8O3 152.15

Benzaldehyde, 4-hydroxy-3-methoxy-.
Vanillin [121-33-5].
» Vanillin contains not less than 97.0 percent and not more than 103.0 percent of C8H8O3, calculated on the dried basis.
Packaging and storage— Preserve in tight, light-resistant containers.
B: Ultraviolet Absorption 197U
Solution: 8 µg per mL.
Medium: methanol.
Melting range 741: between 81 and 83.
Loss on drying 731 Dry it over silica gel for 4 hours: it loses not more than 1.0% of its weight.
Residue on ignition 281: not more than 0.05%.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay— Transfer about 100 mg of Vanillin, accurately weighed, to a 250-mL volumetric flask, add methanol to volume, and mix. Pipet 2 mL of this solution into a 100-mL volumetric flask, add methanol to volume, and mix. Dissolve an accurately weighed quantity of USP Vanillin RS in methanol, and dilute quantitatively and stepwise with methanol to obtain a Standard solution having a known concentration of about 8 µg per mL. Concomitantly determine the absorbances of both solutions in 1-cm cells at the wavelength of maximum absorbance at about 308 nm, with a suitable spectrophotometer, using methanol as the blank. Calculate the quantity, in mg, of C8H8O3 in the portion of Vanillin taken by the formula:
12.5C( A U / A S ),
in which C is the concentration, in µg per mL, of USP Vanillin RS in the Standard solution; and A U and A S are the absorbances of the solution of Vanillin and the Standard solution, respectively.
Auxiliary Information— Staff Liaison : Catherine Sheehan, B.Sc., Scientist
Expert Committee : (EM105) Excipient Monographs 1
USP29–NF24 Page 3455
Phone Number : 1-301-816-8262