Soluble Paracetamol Tablets
Action and use
Analgesic; antipyretic.
Definition
Soluble Paracetamol Tablets contain Paracetamol in a suitable soluble basis.
Content of paracetamol, C8H9NO2
95.0 to 105.0% of the stated amount.
Identification
Tests
Related substances
Carry out the method for liquid chromatography, Appendix III D, using the following solutions. Prepare the solutions immediately before use and protect from light. For solution (1) disperse a quantity of powdered tablets containing 0.2 g of Paracetamol in 8 mL of the mobile phase with the aid of ultrasound, add sufficient mobile phase to produce 10 mL, mix well and filter. For solution (2) dilute 1 volume of solution (1) to 20 volumes with mobile phase and dilute 1 volume of this solution to 20 volumes with mobile phase . Solution (3) contains 0.002% w/v each of 4-aminophenol and paracetamol BPCRS in the mobile phase.Solution (4) contains 0.00002% w/v of 4′-chloroacetanilide in the mobile phase.
The chromatographic procedure may be carried out using (a) a stainless steel column (25 cm × 4.6 mm) packed with octylsilyl silica gel for chromatography (5 µm) (Zorbax Rx C8 is suitable), (b) as the mobile phase with a flow rate of 1.5 mL per minute, with a temperature of 35°C, a mixture of 250 volumes of methanol containing 1.15 g of a 40% v/v solution of tetrabutylammonium hydroxide with 375 volumes of 0.05m disodium hydrogen orthophosphate and 375 volumes of 0.05m sodium dihydrogen orthophosphate and (c) a detection wavelength of 245 nm.
The test is not valid unless, in the chromatogram obtained with solution (3), the resolution factor between the two principal peaks is at least 4.0.
Inject solution (1) and allow the chromatography to proceed for 12 times the retention time of the principal peak. In the chromatogram obtained with solution (1) the area of any peak corresponding to 4-aminophenol is not greater than the area of the corresponding peak in solution (3) (0.1%), the area of any peak corresponding to 4′-chloroacetanilide is not greater than the area of the principal peak in solution (4) (10 ppm) and no other impurity is greater than the area of the principal peak obtained with solution (2) (0.25%).
Assay
Weigh and powder 20 tablets. Add 50 mL of 0.1m sodium hydroxide slowly to a quantity of the powdered tablets containing 0.2 g of Paracetamol. Dilute with 100 mL of water, shake for 15 minutes and add sufficient water to produce 250 mL. Mix, filter and dilute 10 mL of the filtrate to 100 mL with water. Add 10 mL of the resulting solution to 10 mL of 0.1m sodium hydroxide, dilute to 100 mL with water and measure the absorbance of the resulting solution at the maximum at 257 nm, Appendix II B. Calculate the content of C8H9NO2 taking 715 as the value of A(1%, 1 cm) at the maximum at 257 nm.
Storage
Soluble Paracetamol Tablets should be protected from light.