Mono- and Di-glycerides

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

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

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1 DEFINITION

Mono- and Di-glycerides is a mixture of Glycerol mono- and di-esters, with minor amounts of tri-esters, of fatty acids from edible oils. It contains

NLT 40.0% of monoglycerides. The monoglyceride content is NLT 90.0% and NMT 110.0% of the value indicated in the labeling. It may

contain suitable stabilizers.

2 ASSAY

Monoglycerides

Mobile phase: Tetrahydrofuran

Sample solution: 40 mg/mL of Mono- and Di-glycerides in tetrahydrofuran

Chromatographic system

(See Chromatography 〈621〉, System Suitability.)

Mode: LC

Detector: Refractive index

Column: 7-mm × 60-cm; 5-µm packing L21 (100 Å)

[Note—Two or three 7.5-mm × 30-cm L21 columns may be used in place of one 60-cm column provided that System suitability

requirements are met.]

Temperatures

Column: 40°

Detector: 40°

Flow rate: 1 mL/min

Injection volume: 40 µL

System suitability

Sample: Sample solution

[Note—The order of elution is triglycerides, diglycerides, monoglycerides, and glycerin.]

Suitability requirements

Relative standard deviation: NMT 1.0%, determined from the monoglycerides peak

Analysis

Sample: Sample solution

Calculate the percentage of monoglycerides in the portion of Mono- and Di-glycerides taken:

Result = (r_u / r_t) × 100

r_u= peak response for monoglycerides

r_t= sum of the responses of all the peaks, except the solvent peak

Acceptance criteria: 90.0%–110.0% of the value indicated in the labeling

3 IMPURITIES

 Residue on Ignition 〈281〉: NMT 0.1%

Change to read:

▲Arsenic 〈211〉, Procedures, Procedure 2▲ (CN 1-Jun-2023) : NMT 3 µg/g

Limit of Free Glycerin

Mobile phase, Sample solution, and Chromatographic system: Proceed as directed in the Assay for Monoglycerides.

Standard solutions: 0.5, 1.0, 2.0, and 4.0 mg/mL of USP Glycerin RS in tetrahydrofuran

Analysis

Samples: Sample solution and Standard solutions

Measure the responses for the glycerin peaks. Plot the concentration, in mg/mL, of USP Glycerin RS in the Standard solutions versus the

Glycerin peak responses obtained. From the standard curve so obtained, determine the glycerin concentration in the Sample solution.

Calculate the percentage of glycerin in the portion of Mono- and Di-glycerides taken:

Result = (C_u / C_s) × 100

C_u = glycerin concentration in the Sample solution from the standard curve (mg/mL)

C_s= concentration of the Sample solution (mg/mL)

Acceptance criteria: NMT 7.0%

4 SPECIFIC TESTS

Fats and Fixed Oils, Acid Value 〈401〉 : NMT 4

Fats and Fixed Oils, Hydroxyl Value 〈401〉: 90.0%–110.0% of the value indicated in the labeling

Fats and Fixed Oils, Iodine Value 〈401〉: 90.0%–110.0% of the value indicated in the labeling. If the value stated in the labeling is less than 10,

the iodine value is NMT 10.

Fats and Fixed Oils, Saponification Value 〈401〉: 90.0%–110.0% of the value indicated in the labeling

5 ADDITIONAL REQUIREMENTS

Packaging and Storage: Preserve in tight, light-resistant containers.

Labeling: The labeling indicates the monoglyceride content, hydroxyl value, iodine value, saponi[Ký tự không đọc được]cation value, and name and quantity of any

stabilizers.

USP Reference Standards 〈11〉

USP Glycerin RS