Development and Evaluation of MCC-SiO₂/CMC-SiO₂ Conjugates as Tablet Super-Disintegrants

In the present study, microcrystallinecellulose-colloidal silicon dioxide (MCC-SiO₂) and carboxymethylcellulose-colloidal silicon dioxide (CMC-SiO₂) conjugates have been investigated as superdisintegrants in fast dissolving tablets (FDTs). MCC-SiO₂ and CMC-SiO₂ conjugates were prepared and micromeritic studies, FTIR, SEM and XRD methods were utilized for characterizing the powdered conjugates. The conjugates were used for the preparation of domperidone FDTs by direct compression and the wetting time, water absorption ratio, disintegration time and in vitro drug release were evaluated. Effective pore radius of MCC-SiO₂ and CMC-SiO₂ conjugates for 1:1, 1:2.5 and 1:5 was found to be 13.35 ± 0.31 µm, 15.66 ± 0.17 µm and 18.38 ± 0.44 µm, and 16.81 ± 0.24 µm, 20.12 ± 0.39 µm and 26.37 ± 0.24 µm, respectively, compared to 12.21 ± 0.23 µm for MCC and 13.65 ± 0.21 µm for CMC. The results of effective pore radius indicate the wicking capability as well as the disintegration potential of MCC-SiO₂ and CMC-SiO₂ conjugates over pure MCC and CMC. The results of wetting time, water absorption ratio and disintegration time for MCC-SiO₂ conjugates were found to be in the range of 19 ± 1.21 to 30 ± 1.33 s, 42 ± 0.28 to 49 ± 0.47% and 15 ± 2 to 40 ± 1 s, and for CMC-SiO₂ conjugates were found to be in the range of 21 ± 1.13 to 40 ± 1.17 s, 42 ± 0.94 to 49 ± 0.57% and 12 ± 2 to 20 ± 3 s, respectively. Conjugation of MCC and CMC with SiO₂ led to the formation of a complex with remarkable tablet superdisintegrant potential that could be used in preparing fast disintegrating tablets.