Chemical Modifications and their effects on Binding/Disintegrating properties of Plectranthus esculentus starch in Chloroquine Phosphate tablets.

Starch from P.esculentus tubers was extracted and chemically modified using four different methods. Dextrinization of the native starch was done by heating in a hot air oven at 200oC, while hydrolysis was achieved by HCl/ethanol hydrolysis. Gelatinization of the native starch was achieved at 90oC while the starch xerogel was obtained by precipitation with 95% ethanol. Physicochemical characterization of these chemical forms was carried out in comparison with the native starch. These modified forms were then employed as binder/disintegrant (at 5% use level) in chloroquine phosphate tablets.  The results showed that the modified forms of the starch possessed better flow properties compared with the native starch. All batches of tablets gave maximum release of the Active Pharmaceutical Ingredient (API) within 45 min of study except tablets containing the starch xerogel or starch dextrin (200oC). The present study indicated that the starch xerogel or dextrin may be suitable as binders in conventional tablet formulations at low concentrations and may find application as hydrophilic polymer matrices in sustained release tablet formulation.