Meradimate

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

Meradimate contains NLT 95.0% and NMT 105.0% of meradimate (C₁₇H₂₅NO₂).

2 IDENTIFICATION

Change to read:

A. Spectroscopic Identification Tests 〈197〉, Infrared Spectroscopy: 197F (CN 1-May-2020)

Change to read:

B. Spectroscopic Identification Tests 〈197〉, Ultraviolet-Visible Spectroscopy: 197U (CN 1-May-2020)

Sample solution: 5 μg/mL in alcohol

Acceptance criteria: Meets the requirements

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

3 ASSAY

Procedure

Standard solution: 20.0 mg/mL of USP Meradimate RS in tert-butyl methyl ether

Sample solution: 20 mg/mL of Meradimate in tert-butyl methyl ether

Chromatographic system

(See Chromatography 〈621〉, System Suitability.)

Mode: GC

Detector: Flame ionization

Column: 0.32-mm × 25-m; coated with a 0.1-μm film of G1

Temperatures

Injector: 240°

Detector: 260°

Column: See Table 1.

Table 1

Carrier gas: Helium

Flow rate: 6 mL/min

Injection type: Split ratio, 30:1

[Note—The split ratio can be modified to optimize performance.]

Injection volume: 1 μL

System suitability

Sample: Standard solution

Suitability requirements

Relative standard deviation: NMT 2.0%

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of meradimate (C₁₇H₂₅NO₂) in the portion of Meradimate taken:

Result = (r_U/r_S) × (C_S/C_U) × 100

r_U = peak response from the Sample solution

r_S = peak response from the Standard solution

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

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

Acceptance criteria: 95.0%–105.0%

4 IMPURITIES

Organic Impurities

Standard solution, Sample solution, Chromatographic system, and System suitability: Proceed as directed in the Assay.

Analysis

Sample: Sample solution

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

Result = (r_U/r_T) × 100

r_U = peak response of each impurity

r_T = sum of all the peak responses

Acceptance criteria

Any individual impurity: NMT 0.5%

Total impurities: NMT 2.0%

5 SPECIFIC TESTS

Acidity

Sample: 5.0 mL of Meradimate

Titrimetric system

Mode: Direct titration

Titrant: 0.1 N sodium hydroxide VS

Endpoint detection: Visual

Analysis: Transfer 50 mL of alcohol to a suitable container, add 1 mL of phenolphthalein TS, and add sufficient volume of Titrant to obtain a persistent pink color. Transfer 50 mL of this solution to a suitable container, add the Sample, and titrate with Titrant.

Acceptance criteria: NMT 0.2 mL of Titrant per mL of Meradimate is necessary.

Optical Rotation, Specific Rotation〈781S〉: −4° to +4°

Sample solution: 10 mg/mL in alcohol

Refractive Index 〈831〉: 1.540–1.544 at 20°

6 ADDITIONAL REQUIREMENTS

Packaging and Storage: Preserve in tight containers.

USP Reference Standards 〈11〉

USP Meradimate RS