Nabumetone Tablets

Action and use

Cyclo-oxygenase inhibitor; analgesic; anti-inflammatory.

Definition

Nabumetone Tablets contain Nabumetone.

Content of nabumetone, C₁₅H₁₆O₂

95.0 to 105.0% of the stated amount.

Identification

The infrared absorption spectrum of the powdered tablets, Appendix II A, is concordant with the reference spectrum of nabumetone (RS 239).

Related substances

Comply with the test described under Nabumetone Oral Suspension but using a solution prepared in the following manner as solution (1). Shake a quantity of the powdered tablets containing 0.25 g of Nabumetone with 50 mL of acetonitrile for 5 minutes, filter through a glass-fibre filter (Whatman GF/C is suitable) and use the filtrate.

Assay

Carry out the method for liquid chromatography, Appendix III D, using the following solutions. For solution (1) finely powder a quantity of whole tablets containing 5 g of Nabumetone, add 400 mL of acetonitrile, mix with the aid of ultrasound for 15 minutes, allow to cool, add sufficient acetonitrile to produce 500 mL, mix and filter through a glass-fibre filter (Whatman GF/C is suitable). Dilute 5 volumes of the filtrate to 100 volumes with the mobile phase and further dilute 5 volumes of the resulting solution to 50 volumes with the mobile phase. For solution (2) dilute 5 volumes of a 0.1% w/v solution of nabumetone BPCRS in acetonitrile to 100 volumes with the mobile phase.

The chromatographic procedure may be carried out using (a) a stainless steel column (15 cm × 4.6 mm) packed with base-deactivated octadecylsilyl silica gel for chromatography (4 µm) (Genesis C18 4µ is suitable), (b) a mixture of 18 volumes of tetrahydrofuran, 40 volumes of a 0.1% v/v solution of glacial acetic acid in carbon dioxide-free water and 42 volumes of acetonitrile for chromatography as the mobile phase with a flow rate of 1 mL per minute and (c) a detection wavelength of 254 nm. When the chromatograms are recorded under the prescribed conditions the retention time of nabumetone is about 4 minutes.

Calculate the content of C₁₅H₁₆O₂ in the tablets from the chromatograms obtained using the declared content of C₁₅H₁₆O₂ in nabumetone BPCRS.