Evaluation of Okra gum as a binder in tablet dosage forms

Abstract

The type and the amount of binders decisively influence the characteristics of tablets prepared by wet granulation procedure. Commonly used binders like acacia, gelatin, starch and hydrolyzed starch have natural origin. The aim of this study was to evaluate the effectiveness of a new binder extracted from Hibiscus esculentus (Okra gum) in tableting. binder Hibiscus esculentus gum was extracted from the pods of okra fruit by maceration in distilled water followed by filtration of viscous solution as well as precipitation of gum extract by using acetone. To evaluate the binder effectiveness, two models including a placebo formulation (lactose) and a drug formulation (acetaminophen, ibuprofen, and/or calcium acetate) were evaluated. Granules were prepared by different concentrations (0.5-6%) of Okra gum and tabletted using a Kilian single punch press. Cornstarch (12.5%) and P.V.P (22%) were employed as the standard binders for comparison. The physical properties of the granulates and those of the tablets including disintegration time and dissolution rate were studied. The dissolution studies of tablets were performed in order to evaluate the role of binder in drug release in comparison with common binders. The properties of placebo granulates (bulk and tapped density, granule strength, flowability) as well as those of tablets (hardness, friability, disintegration time) were generally good. However the physical properties of ibuprofen and calcium acetate tablets containing Okra gum showed sufficient hardness (breaking load 55 N and 59.3 N), slow disintegration (completed after 35 min and 24 min) and low friability. The results showed that the drug release from tablets containing Okra gum significantly decreased (p