FORMULATION AND EVALUATION OF MUCOADHESIVE TABLETS OF METRONIDAZOLE USING ACID MODIFIED MUCIN

*Sylvester Okhuelegbe Eraga, Matthew Ikhuoria Arhewoh, Rebecca Eboisiegbe Obazeiki and Magnus Amara Iwuagwu

ABSTRACT

The objective of this study was to determine the effect of acid treatment of mucin on the mucoadhesive properties and tablet parameters of metronidazole tablets. Mucin was extracted from the African giant snails (Archachatina maginata) by differential precipitation using acetone, air-dried and pulverized. Different portion of the mucin powder was treated with mineral acids (hydrochloric and nitric acids) and organic acid (acetic acid) at high and low concentrations and at varied times of 1 and 12 h. Ten batches of metronidazole tablets (M1-M10) were prepared with the modified mucin by direct compression. Their granules and tablets were evaluated for flow properties and tablets parameters respectively. Tablet mucoadhesion was determined using the mass flow rate method. All the batches of granules gave good flow characteristics with their angles of repose < 30°. The formulated tablets passed the weight variation test with hardness values within the range of 3.0 to 5.0 kp and friability of 0.7 to 2.9 % while the content of active drug met official compendial requirements. Tablets of HCl treated mucin gave mucoadhesion values of 2.80 g/sec irrespective of HCl concentration and time. This value was higher than those of the unmodified mucin tablets which gave 0.75 g/sec. Tablets of mucin treated by other acids gave mucoadhesion values of 0.39 g/sec, 0.46 g/sec and 0.19 g/sec for batches M7, M8 and M9 respectively. Tablets of mucin treatment using HCl gave improved mucoadhesive properties compared to the unmodified mucin. Thus, this knowledge can be improved upon to enhance the formulation of mucoadhesive dosage forms.

Keywords: acid treatment, mucin, mucoadhesion, tablets, metronidazole.