Liquid chromatographic determination of primidone in tablets: collaborative study.

Area of Science:

• Pharmaceutical Analysis
• Analytical Chemistry
• Chromatographic Methods

Background:

• Primidone is an anticonvulsant medication used to treat epilepsy.
• Accurate quantification of primidone in pharmaceutical formulations is crucial for patient safety and therapeutic efficacy.
• Standardized analytical methods are required for regulatory compliance and quality control.

Purpose of the Study:

• To collaboratively validate a liquid chromatographic (LC) method for the quantitative determination of primidone in tablet dosage forms.
• To assess the accuracy, precision, and reliability of the proposed LC method across multiple laboratories.
• To establish an official method for primidone analysis in pharmaceutical products.

Main Methods:

• A liquid chromatographic (LC) method was developed and tested by six independent laboratories.
• Collaborators analyzed commercial primidone tablets (50 and 250 mg) and authentic mixtures at specified levels.
• Samples were prepared by dissolving in the mobile phase, followed by filtration and chromatographic injection.

Main Results:

• The LC method demonstrated high average recoveries, ranging from 97.5% to 101.2% across all tested samples.
• Excellent precision was observed, with coefficients of variation ranging from 0.53% to 3.01%.
• The method proved robust and reproducible across the participating laboratories.

Conclusions:

• The validated LC method provides accurate and precise quantitative determination of primidone in tablets.
• The method's performance supports its adoption as an interim official first action method.
• This standardized method enhances quality control for primidone-containing pharmaceuticals.