Formulation Optimization and Evaluation of Nanoemulsion Loaded with Plant Extract of Crinum Latifolium for Antiarthritic Potential

Abstract

Crinum Latifolium (CL) is a well-known plant known for its anti-oxidant, anti- inflammatory and anti-arthritic activity belonging to family Amaryllidaceae. Leaves part of that has tremendous anti-arthritic activity. The objective of this study was to formulate a nanoemulsion formulation from methanolic extract of Crinum Latifolium for the treatment of rheumatoid arthritis (RA) with the intention of minimizing the systemic side effects via oral delivery. First, the methanolic extract of Crinum Latifolium (MCL) was obtained by Maceration method. The nanoemulsion formulation of Crinum Latifolium methanolic extract (NE-MCL) was prepared through the hot emulsification followed by homogenization technique. The optimization of surfactant and co-surfactant concentration was carried out using phase diagrams method and found that is able to formulate a stable emulsion. This ratio was further investigated for the process parameters i.e. Oil: Smix (X1), stirring speed (X2), and stirring time (X3). The final optimized formulation was found to have particle size (PS) of 225 nm, polydispersity index of 0.128 and zeta potential of -3.198mV with a desirability of 0.846. The optimized formulation was consisted of 98.33 ± 0.69% drug content. In vitro drug release studies showed that about 80% of the MCL was released in 24 hrs from the NE-MCL represented its sustained release effect. The TEM micrograph showed a perfectly spherical shaped particles in nano size range. The in vitro drug release of nanoemulsion formulation was compared to plain drug solution and found that nanoemulsion showed a better sustained release effect compared to plain drug solution. Also, the  R² value for zero order, first order, Higuchi model and Koresmeyer Peppas model was  found to be 0.782, 0.815, 0.912 and 0.892 respectively which showed that the drug was released by diffusion-controlled mechanism from the matrix. These results showed that nanoemulsion formulation is capable to provide a sustained release formulation which in turn helped in reducing the dosage and dosing frequency and thereby, reduces the adverse effects of MCL.