Purpose: To determine the potential
of some anionic exchange resins as tablet disintegrants.
Methods: Dowex1® x2, x4 and x8
resins (crosslinked copolymers of styrene and
divinylbenzene with quaternary methyl amine
functionality) were evaluated as disintegrant for
dibasic calcium phosphate dihydrate tablets. The best
resin providing the fastest disintegration and highest
hardness of obtained tablets was selected for further
investigation. The effect of resin concentration and
compression force on the properties of tablets using the
selected resin was investigated. In addition, the
disintegrant efficacy of the selected resin in the
tablet formulations containing either a basic drug,
e.g., dextromethorphan hydrobromide (DMP), or an acidic
drug, e.g., diclofenac sodium (DCN), was determined in
comparison with sodium starch glycolate (SSG).
Results: Dowex1®x2 resin exhibited
the fastest disintegration (6.0 s) and the highest
hardness (103.6 N) of obtained tablets. These
disintegrating and tablet properties depended upon the
resin concentration and compression force. For DMP, the
resin provided faster disintegration and drug release
(8.0 s and 100.4 % at 10 min) as compared with SSG (16.2
s and 98.9 % at 30 min). In contrast, the resin caused
the depleted release of DCN (61.6 % at 120 min) in spite
of providing the faster tablet disintegration (10.0 s)
than SSG (15.5 s) due to the ionic binding of the drug
and resin.
Conclusion: The Dowex1®x2 resin was
shown to be a potential disintegrant for the tablets of
basic drugs.
Keywords: Anionic exchange resin,
Disintegrant, Dextromethorphan hydrobromide, Diclofenac
sodium, Calcium phosphate