Formulation, in Vitro Characterization and Anti- Tuberculosis Investigation of Isoniazid Nanocapsules

Abstract Purpose Tuberculosis (TB) is a major cause of mortality worldwide. The most commonly used first-line anti-TB drugs in the treatment of TB are rifampicin and isoniazid. The aim of this study was to formulate and evaluate the anti-mycobacterium activity of isoniazid (INH) nano formulations against mycobacterium isolates (M. smegmatis and M. bovis). Methods A 10 g quantity of the lecithin powder was placed in a beaker and 50 mL quantity of water added and heated on a water bath at 55oC for 30 minutes. The oil and water phases were separated by centrifugation at 3000 rpm for 30 minutes. The gum/crude lecithin was dried in vacuum oven for 1 hour at 40 oC. The solvent and lecithin were separated by decantation. The acetone was removed by heating at low temperature at 40 oC and the powdered lecithin was packaged in screw-capped containers until further use. Results The percentage yield of the extracted lecithin ranged from 31.0±0.31% to 35.0±0.32%. The differential scanning calorimetry (DSC) thermograph of pure INH was 121.8oC. The drug content of isoniazid formulation using extracted lecithin (IEL) and isoniazid formulation using reference lecithin (IRL) ranged from 96.4±0.29% to 93.5±0.94% respectively. The INH nano capsule formulations showed significantly (p < 0.05) lower MICs (0.03 µg/mL) than the reference commercial capsule of INH (0.05 and 0.10 µg/mL) against M. smegmatis and M. bovis isolates, respectively. Conclusion The chitosan-fortified nano capsule formulation of INH has potentials for further exploration and development for enhanced bioavailability and application against MDR-TB.