Triacetin

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

C₉H₁₄O₆               218.21

1,2,3-Propanetriol triacetate;

Triacetin;

Glyceryl triacetate     CAS RN^®: 102-76-1.

1 DEFINITION

Triacetin contains NLT 97.0% and NMT 102.0% of triacetin (C,H,O), calculated on the anhydrous basis.

2 IDENTIFICATION

Change to read:

A. ^▲SPECTROSCOPIC IDENTIFICATION TESTS (197), Infrared Spectroscopy: 197F_{▲(CN 1-MAY-2020)}

B. The retention time of the triacetin peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.

3 ASSAY

PROCEDURE

Internal standard solution: 0.1 mg/mL of benzyl alcohol in 2-propanol

Standard solution: 0.25 mg/mL of USP Triacetin RS in Internal standard solution

Sample solution: 0.25 mg/mL of Triacetin in Internal standard solution

Chromatographic system

(See Chromatography (621), System Suitability.)

Mode: GC

Detector: Flame ionization

Column: 0.25 - mm x 30 - m coated with a 0.25-µm film of phase G46

Temperatures

Injection port: 200°

Detector: 250°

Column: See Table 1.

Table 1

Carrier gas: Hydrogen

Flow rate: 1.5 mL/min

Injection volume: 1 µL

Injection type: Split ratio, 40:1

System suitability

Sample: Standard solution

[NOTE-The relative retention times for benzyl alcohol and triacetin are 0.7 and 1.0, respectively.]

Suitability requirements

Tailing factor: NMT 2.0 for the triacetin peak

Relative standard deviation: NMT 1.0%, peak response ratio of triacetin to benzyl alcohol

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of triacetin (C₉H₁₄O₆) in the portion of Triacetin taken:

                         Result = (R_U/R_S) × (C_S/C_U) × 100

R_U = peak response ratio of triacetin to benzyl alcohol from the Sample solution

R_S = peak response ratio of triacetin to benzyl alcohol from the Standard solution

C_S = concentration of USP Triacetin RS in the Standard solution (mg/mL)

C_U = concentration of Triacetin in the Sample solution (mg/mL)

Acceptance criteria: 97.0%-102.0% on the anhydrous basis

4 IMPURITIES

ORGANIC IMPURITIES

Internal standard solution: 0.02 mg/mL of benzyl alcohol in 2-propanol

Peak identification solution: 0.25 mg/mL each of glycerol, monoacetin, diacetin, and USP Triacetin RS in Internal standard solution

Standard solution: 0.02 mg/mL of USP Triacetin RS in Internal standard solution

Sample solution: 20 mg/mL of Triacetin in Internal standard solution

Chromatographic system

(See Chromatography (621), System Suitability.)

Mode: GC

Detector: Flame ionization

Column: 0.25 - mm x 30 - m coated with a 0.25-µm film of phase G46

Temperatures

Injection port: 200°

Detector: 250°

Column: See Table 2.

Table 2

Carrier gas: Hydrogen

Flow rate: 1.5 mL/min

Injection volume: 1 µL

Injection type: Split ratio, 40:1

System suitability

Sample: Standard solution

[NOTE-The relative retention times for benzyl alcohol and triacetin are 0.62 and 1.0, respectively.]

Suitability requirements

Tailing factor: NMT 2.0 for the triacetin peak

Relative standard deviation: NMT 5.0%, peak response ratio of triacetin to benzyl alcohol.

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of each impurity in the portion of Triacetin taken:

                         Result = (R_U/R_S) × (C_S/C_U) × (1/F) x 100

R_U = peak response ratio of each impurity to benzyl alcohol from the Sample solution

R_S = peak response ratio of triacetin to benzyl alcohol from the Standard solution

C_S = concentration of USP Triacetin RS in the Standard solution (mg/mL)

C_U = concentration of Triacetin in the Sample solution (mg/mL)

F = relative response factor (see Table 3)

Acceptance criteria: See Table 3. Reporting threshold: 0.05%.

Table 3

5 SPECIFIC TESTS

WATER DETERMINATION (921), Method I: NMT 0.2%

6 ADDITIONAL REQUIREMENTS

PACKAGING AND STORAGE: Preserve in tight containers.

USP REFERENCE STANDARDS (11)

USP Triacetin RS