The Effects of Lubricants on the Disintegration and Dissolution Profile of Metronidazole Tablets Formulated Using Sida acuta Gum as a Binder

Aims: This research was done to study the effects of types and concentrations of lubricants on the dissolution and disintegration profile of metronidazole tablets formulated using Sida acuta gum as a binder.

Methodology: Sida acuta gum (SAG) was extracted from powdered dried leaves of Sida acuta. Metronidazole granules were produced by wet granulation technique using different concentrations (1 and 2%) of SAG as a binder and mixed with different concentrations (0.5, 1.0, and 1.5%) of magnesium stearate (MS) or sodium lauryl sulphate (SLS) as a lubricant. The granules/lubricant -mix was compressed into tablets and evaluated for hardness, weight uniformity, drug content, disintegration time, friability and in vitro drug release.

Results: The hardness for the tablets was from 4.08 to 7.97 Kgf. The friability was from 0.02±0.45 to 3.40±0.43%. Tablets from formulations A1-A3, B2, and B3 failed the friability test. Formulations prepared with 1% SAG were more friable than those formulated with 2% SAG. Disintegration time for formulations A1-A3 (1% SAG + MS) ranged from 19.07 to 63.5 min, while that of A4-A6 (2% SAG + MS) was from 39.06 to 81.48 min. Formulations B1-B3 (1% SAG + SLS) had disintegration time that ranged from 4.22 to 6.8 min while that of B4-B6 (2% SAG + SLS) was from 9.35 to 15.90 min. The % drug release at 60 min for formulations that contained SAG and MS was 76.60-104.28% and SAG and SLS was 99.89-101.35%

Conclusion: Metronidazole tablets formulated using SLS as lubricant disintegrated faster than those formulated using magnesium stearate as lubricant. Percentage drug release from tablets containing SLS was slightly higher than those that contained magnesium stearate. Higher concentrations of the lubricants produced softer tablets.