Formation of bioresorbable PCL-loaded Moringa Oleifera L./Natural clay functional particles by solvent displacement method for pharmaceutical applications

Bioresorbable functional particles offer unique advantages based on different synthetic strategies, with the activated moiety may achieve various targeted drug delivery to minimize side effects. Thus, in this study, a highly MO-loaded adsorptive smart-assembled natural clay (montmorillonite, MMT) dispersion onto poly (ε-caprolactone) nanoparticles matrix (hereafter known as MO-loaded MMT/PCL NPs) is formed by solvent displacement method. MMT is selected due to its great drug loading ability due to high specific surface area and grants mucoadhesive properties with tortuous pathway needed for drug delivery across the gastrointestinal barrier. The MO-loaded MMT/PCL NPs are synthesized by self-solvation interaction between the organic phase that composed of dissolved 1 g L−1 PCL, 2–20 wt % of MMT, and 0.6–3.0 g L−1 of MO in acetone and the aqueous phase consisted of 0.2 wt% poly (vinyl alcohol) surfactant solution. The injection rate of organic phase was fixed at 5 mL min−1 with volume ratio aqueous phase to organic phase (Vaq/Vor) between 3–10, and 600–1200 rpm of stirring speed. The inclusion of MMT in polymer was found to improve the entrapment of hydrophilic MO, hence hindering untimely drug leakage. Particle size decreased with increasing the stirring rate and the aqueous-to-organic volumetric ratio as well as the concentration MMT, thus resulting in drug encapsulation efficiency and drug loading up to 30–50 and 5–10%, respectively. The encapsulation of MMT and MO in the NPs was confirmed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy.