Diclofenac potassium Tablets (Assay) (By HPLC) | Finished Product | Test Procedure | Method of analysis (MOA) |

Solution A:  0.01 M phosphoric acid and 0.01 M monobasic sodium phosphate (1:1). If necessary, adjust with additional portions of the appropriate components to a pH of 2.5 (± 0.2). Mobile phase :  Methanol and Solution A (7:3) Diluent :  Methanol and water (7:3) Standard solution: Take 50 mg of Diclofenac Potassium working Standard in 100 ml volumetric flask, add 70ml Diluent  sonicate it half an hours, remaining volume makeup with Diluent. Sample solution:  Weigh and finely powder NLT 20 Tablets. Transfer a portion of the powder, nominally equivalent to 50 mg of diclofenac potassium, to a 100-mL volumetric flask. Add 70 mL of Diluent, stir for 60 min, dilute with Diluent to volume, mix, and centrifuge. CHROMATOGRAPHIC CONDITIONS    (a) Column :  4.6-mm × 25-cm; 5-µm packing L7  (b) Use isocratic  elution and the mobile phase described as above    (c) Use a  flow rate of 1.0 mL per minute.    (d) Use an  ambient column temperature.     (e) Use a  detection wavelength of 254 nm.    (f) Inject  20 µL of each solution. Calculation: