فهرست نشریات علمی دسترسی آزاد ایران

This study aims to develop sodium alginate based microspheres crosslinked with CaCl₂ as a drug delivery system for silymarin, a compound with low water solubility. The goal to evaluate the microspheres’ ability to release silymarin under different concentrations and pH conditions. Microspheres were prepared and characterized using Scanning Electron Microscopy (SEM), Fourier-transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and a Particle Size Analyzer (PSA). Scanning Electron Microscopy (SEM), Fourier-transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Particle Size Analyzer (PSA). Entrapment efficiency (%EE) and drug release were measured. Characterization showed that the microspheres were nearly spherical with a slightly porous surface and had a particle size range of 0.295–0.531 μm. FTIR confirmed the presence of sodium alginate functional groups (C=O, C–O), Ca–O bonds, and the aromatic C=C of silymarin. XRD analysis indicated an amorphous structure. The highest %EE was observed at 500 ppm (72.07%). Dissolution studies showed that 100 ppm released 95.04%, 300 ppm released 47.83%, and 500 ppm  released 18.00% at 240 minutes. pH variation tests indicated releases of 31.94% (pH 1.2), 44.12% (pH 5.0), and 51.32% (pH 7.4). Release kinetics followed the Korsmeyer–Peppas model for 100 ppm (r² = 0.9907, n = 0.8213) and 300 ppm (r² = 0.9762, n = 0.7200), and the Higuchi model for 500 ppm (r² = 0.9428). For pH variation, release followed first-order kinetics at pH 1.2 (r² = 0.8313), while at pH 5.0 (r² = 0.9547, n = 0.6973) and pH 7.4 (r² = 0.9777, n = 0.7197) it followed the Korsmeyer–Peppas model.