Ulcerative colitis (UC) is a chronic inflammatory colon disorder. Several modern medicines have been used for UC treatment but are associated with side effects. Hence, herbal medicine-inspired lead molecules are promising for managing UC. Chlorogenic acid (CGA), an herbal bioactive, has been reported for anti-inflammatory, anticancer, antioxidant, and immunomodulatory activity. The current study aimed to develop enteric-coated mucoadhesive beads of CGA for colon targeting. CGA-loaded beads were prepared using chitosan and carrageenan as polymers through an ionic gelation technique. Furthermore, beads were coated with Eudragit S-100. The formulations were characterized by particle size analyzer, ultraviolet (UV)-spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and in vitro drug release study. The optimized formulation (CGA-F2) showed particle size (440.6 ± 6.1 μm), zeta potential (-31.12 ± 2.16 mV), entrapment efficiency (83.56 ± 5.46), %yield (86.87 ± 4.19), and drug loading (1.14 ± 0.09). SEM indicated that the morphologies of CGA-F2 were spherical and ellipsoidal. The FTIR study confirmed the compatibility of the drug with polymers used in the formulations. CGA-F2 exhibited mucoadhesive efficiency (94.33 ± 2.1%) and swelling index (0.98 ± 0.03) at simulated colonic fluid (SCF) pH 7.4 (***p < 0.001) significantly. In an in vitro drug release study, CGA-F2 (95.07 ± 3.85%) showed a sustained drug release profile in SCF (pH 7.4) at 37 ± 0.5°C for 24 h. Optimized formulation exhibited drug release in a sustained manner for 24 h, which may be due to the effect of mucoadhesive and enteric coating polymer. Hence, CGA-loaded beads would be promising for treating the UC.
Keywords: Eudragit S-100; beads; chitosan; chlorogenic acid; colon; mucoadhesion; ulcerative colitis.