Panthenol

This article is compiled based on the United States Pharmacopeia (USP) – 2025 Edition

Issued and maintained by the United States Pharmacopeial Convention (USP)

DOWNLOAD PDF HERE

C₉H₁₉NO₄ 205.25

Butanamide, 2,4-dihydroxy-N-(3-hydroxypropyl)-3,3-dimethyl-, (±)-;

(±)-2,4-Dihydroxy-N-(3-hydroxypropyl)-3,3-dimethylbutyramide;

(±)-Pantothenyl alcohol CAS RN^®: 16485-10-2; UNII: WV9CM0O67Z.

1 DEFINITION

Panthenol is a racemic mixture of the dextrorotatory and levorotatory isomers of panthenol. It contains NLT 99.0% and NMT 102.0% of racemic panthenol (C₉H₁₉NO₄), calculated on the dried basis.

2 IDENTIFICATION

Change to read:

A. SPECTROSCOPIC IDENTIFICATION TESTS (197), Infrared Spectroscopy: 197M (CN 1-MAY-2020)

B.

Sample solution: 100 mg/mL of Panthenol

Analysis: To 1 mL of the Sample solution add 5 mL of 1 N sodium hydroxide and 1 drop of cupric sulfate TS, and shake vigorously.

Acceptance criteria: A deep blue color develops.

C.

Sample solution: 10 mg/mL of Panthenol

Analysis: To 1 mL of the Sample solution add 1 mL of 1 N hydrochloric acid, and heat on a steam bath for 30 min. Cool, add 100 mg of hydroxylamine hydrochloride, and add 5 mL of 1 N sodium hydroxide. Allow to stand for 5 min, then adjust with 1 N hydrochloric acid to a pH of 2.5-3.0, and add 1 drop of ferric chloride TS.

Acceptance criteria: A purplish red color develops.

3 ASSAY

3.1 PROCEDURE

0.1 M potassium biphthalate: Transfer 20.42 g of potassium biphthalate into a 1000-mL volumetric flask, and add sufficient glacial acetic acid to dissolve. If necessary, warm the mixture on a steam bath to achieve complete solution, observing precautions against absorption of moisture. Cool to room temperature, and dilute with glacial acetic acid to volume.

Sample: 400 mg of Panthenol

Blank: Proceed as directed in the Analysis, omitting the Sample.

Titrimetric system

(See Titrimetry (541).)

Mode: Residual titration

Titrant: 0.1 N perchloric acid VS

Back-titrant: 0.1 M potassium biphthalate

Endpoint detection: Visual

Analysis: Transfer the Sample to a 300-mL flask fitted to a reflux condenser by means of a standard-taper glass joint, add 50.0 mL of Titrant, and reflux for 5 h. Cool, observing precautions to prevent atmospheric moisture from entering the condenser, and rinse the condenser with glacial acetic acid, collecting the rinsings in the flask. To the flask add 5 drops of crystal violet TS, and titrate with the Back-titrant to a blue-green endpoint. Perform the Blank determination.

Calculate the percentage of panthenol (C₉H₁₉NO₄) in the Sample taken:

Result = {[(V_B - V_S) x M x F]/W} x 100

V_B = Back-titrant volume consumed by the Blank (mL)

V_S = Back-titrant volume consumed by the Sample (mL)

M = actual molarity of the Back-titrant (mM/mL)

F = equivalency factor, 205.3 mg/M

W = Sample weight (mg)

Acceptance criteria: 99.0%-102.0% on the dried basis

4 IMPURITIES

4.1 RESIDUE ON IGNITION (281)

NMT 0.1%

4.2 LIMIT OF AMINOPROPANOL

Sample: 10 g of Panthenol

Blank: 25 mL of water

Titrimetric system

(See Titrimetry (541).)

Mode: Direct titration

Titrant: 0.01 N sulfuric acid VS

Endpoint detection: Visual

Analysis: Dissolve the Sample in 25 mL of water, and add bromothymol blue TS. Titrate with the Titrant to a yellow endpoint. Perform the Blank determination.

Calculate the percentage of aminopropanol in the Sample taken:

Result = {[(V_S - V_B) x N x F]/W} x 100

V_S = Titrant volume consumed by the Sample (mL)

V_B = Titrant volume consumed by the Blank (mL)

N = actual normality of the Titrant (mEq/mL)

F = equivalency factor, 75.11 mg/mEq

W = Sample weight (mg)

Acceptance criteria: NMT 0.10%

5 SPECIFIC TESTS

5.1 MELTING RANGE, Class (741)

64.5°-68.5°

5.2 OPTICAL ROTATION, Specific Rotation (781S)

Sample solution: 50 mg/mL in water

Acceptance criteria: -0.05° to +0.05°

5.3 LOSS ON DRYING (731)

Dry a sample in a vacuum over phosphorus pentoxide at 56° for 4 h: it loses NMT 0.5% of its weight.

6 ADDITIONAL REQUIREMENTS

6.1 PACKAGING AND STORAGE

Preserve in tight containers.

6.2 USP REFERENCE STANDARDS (11)

USP Racemic Panthenol RS