Pyrazinamide Tablets
Action and use
Antituberculosis drug.
Definition
Pyrazinamide Tablets contain Pyrazinamide.
Content of pyrazinamide, C5H5N3O
95.0 to 105.0% of the stated amount.
Identification
Shake a quantity of the powdered tablets containing 0.25 g of Pyrazinamide with 20 mL of absolute ethanol, filter, evaporate the filtrate to dryness and dry the residue at 105° for 30 minutes. The infrared absorption spectrum of the residue, Appendix II A, is concordant with the reference spectrum of pyrazinamide (RS 306).
Related substances
Carry out the method for thin-layer chromatography, Appendix III A, using the following solutions.
20 volumes of glacial acetic acid, 20 volumes of water and 60 volumes of butan-1-ol.
Any secondary spot in the chromatogram obtained with solution (1) is not more intense than the spot in the chromatogram obtained with solution (2) (0.2%).
Assay
Weigh and powder 20 tablets. To a quantity of the powder containing 0.1 g of Pyrazinamide add 200 mL of water, allow to stand for 10 minutes, swirling occasionally, mix with the aid of ultrasound for 10 minutes and dilute to 500 mL with water. Filter and discard the first 20 mL of filtrate. Dilute 5 mL of the filtrate to 100 mL with water and measure the absorbance of the resulting solution at the maximum at 268 nm, Appendix II B. Calculate the content of C5H5N3O taking 650 as the value of A(1%, 1 cm) at the maximum at 268 nm.