Mesalamine loaded ethyl cellulose nanoparticles: optimization and in vivo evaluation of antioxidant potential in ulcerative colitis

This study aimed to optimize mesalamine (MES)-nanoparticles (NPs) using Box Behnken Design and investigate its<i>in vivo</i>antioxidant potential in colon drug targeting. The formulation was prepared using oil/water (O/W) emulsion solvent evaporation technique for time dependent colonic delivery. The optimal formulation with the following parameters composition was selected: polymer concentration (% w/w) (A) = 0.63, surfactant concentration (% w/w) (B) = 0.71, sonication duration (min) (C) = 6. The outcomes showed that ethyl cellulose (EC) NP containing MES has particles size of 142 ± 2.8 nm, zeta potential (ZP) of -24.8 ± 2.3 mV, % EE of 87.9 ± 1.6%, and PDI of 0.226 ± 0.15. Scanning electron microscopy revealed NPs has a uniform and spherical shape. The<i>in-vitro</i>release data disclosed that the EC NPs containing MES showed bursts release of 52% ± 1.6% in simulated stomach media within 2 h, followed by a steady release of 93% ± 2.9% in simulated intestinal fluid that lasted for 48 h. The MES release from NP best match with the Korsmeyer-Peppas model (<i>R</i>²= 0.962) and it followed Fickian diffusion case I release mechanism. The formulation stability over six-months at 25 °C ± 2 °C with 65% ± 5% relative humidity, and 40 °C ± 2 °C with 75% ± 5% relative humidity showed no significant changes in colour, EE, particle sizes and ZP. As per<i>in vivo</i>results, MES-NP effectively increased glutathione, SOD level and reduces the LPO level as compared to other treatment groups. The findings hold promise that the developed formulation can suitably give in ulcerative colitis.