Superdisintegrant absorbs water by wicking or capillary action, undergoes swelling, induces hydrodynamic pressure in the
tablet core leading to disintegration. Moreover, they can be functional in accelerating drug release by producing finer
particles of higher specific surface area available for interaction with dissolution medium. Disintegrant activity, however,
may be influenced by the hydrophilicity of the filler excipient. In the present experimental work, soluble diluent, lactose and
hygroscopic, insoluble diluent, di-calcium phosphate dihydrate, were combined with superdisintegrant, Ac-di-sol to produce
tablets of Danazol solid dispersion and evaluated for their effects on the water absorption percentage, disintegration time and
release kinetics. High hydrophilicity and fibrous nature of Ac-Di-Sol resulted in water absorption percentages of 60% and
52% into the tablet structure for the batches DZ-SDT(L)-2 and DZ-SDT(D)-2 respectively. Use of di-calcium phosphate
dihydrate as filler in tablet containing 8% w/w of Ac-di-sol as suerdisintegrant imparted a matrix characteristic to tablet of
Danazol solid dispersion which absorbed water sufficiently, followed by quite rapid disintegration, release of 60% of drug
within 8 mins and 6-fold lowering in Mean Dissolution Time value. Therefore, proper combination of filler and
superdisintegrant is crucial to achieve desired disintegration characteristics and release profile of drug from solid dispersion
tablets of a BCS Class II drug.
Key words: Superdisintegrant, filler hydrophilicity, water absorption percentage, release kinetics
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