Formulation of Lecithin-Based Nanocapsules of Levofloxacin and In Vitro Evaluation of the Anti-Mycobacterium Potentials

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis. Multidrug resistant TB (MDR-TB) remains a public health crisis. The aim of this study was to formulate and evaluate the anti-mycobacterium activity of levofloxacin (LVF) nano formulations against mycobacterium isolates.  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. 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 LVF showed two sharp endothermic peaks at 225.7oC and 227.8oC. The drug content of levofloxacin formulation using extracted lecithin (LEL) and levofloxacin formulation using reference lecithin (LRL) ranged from 96.9±0.17% to 98.6±0.12% respectively. The LVF nano capsules had activities against the mycobacterial isolates with minimum inhibitory concentrations (MICs) of 26.9μg/mL for LEL and 58.3μg/mL for LRL. The chitosan-fortified nano capsule formulation of LVF has potentials for further exploration and development for enhanced bioavailability and application against MDR-TB.