A COLLABORATIVE STUDY OF THE IN-VITRO DISSOLUTION OF ACETYLSALICYLIC-ACID GASTRO-RESISTANT CAPSULES COMPARING THE FLOW-THROUGH CELL METHOD WITH THE USP PADDLE METHOD

A collaborative in vitro dissolution study was performed comparing the Flow-through cell (FTC) method with the USP Paddle method. The object ive was to compare the two methods regarding their suitability for cha nging the pH of a dissolution medium and for measuring the in vitro di ssolution of a gastro-resistant dosage form. Aspirin, a gastro-irritan t substance in an enteric-coated, multiple-unit dosage form, was used as the test material. The results show that the FTC method gives compa rable results compared with the Paddle method. The FTC method is also more convenient to use for shifting the pH from an acidic condition at pH 1.2 to a pH of 6.8. The effect of different ionic strengths of the dissolution media on dissolution rate results was observed for the te st product by using the FTC method. (C) 1997 Elsevier Science B.V.