Improved technological performance of benecel K4M/Carbopol 971P NF matrices with Avicel DG

Carbopol 971P NF is a polymer applied to controlled release formulations with a poor flowability as its main drawback. The aim of this work is the use of Avicel DG to improve the powder flowability maintaining the technological performance of formulations containing this polymer. Mixtures containing metronidazole with 15% Carbopol 971P NF, 15% Bencel K4M, and different proportions of Avicel DG were evaluated in their powder flowability and compactibility as powders and dry granulations, while the release profiles were examined in their tablets. Avicel DG improves sufficiently the powder flowability only after dry granulation. Moreover, it increases the formulations compactibility as its proportion in the formulations increases. The compactibility of the powders is reduced in a lesser proportion after dry granulation. Avicel DG reduces the efficiency of the polymeric matrices to restrict the metronidazole release, however, dry granulation recovers it partially. The release mechanism is maintained in all cases as an anomalous process.