Programmed pH-responsive core-shell nanoparticles for precisely targeted therapy of ulcerative colitis

pH-Responsive nanotherapeutics were recently developed for the treatment of ulcerative colitis (UC). However, they target the entire colon rather than the UC site, which leads to insufficient accumulation in inflamed colon lesions and causes side effects. Core-shell nanoparticles exhibit unique advantages in improving the precision of targeted delivery. In this study, Eudragit® EPO and L100, two pH-sensitive materials, were coated on nano-sized curcumin to fabricate core-shell nanoparticles. The developed CNs@EPO@L100 exhibited programmed pH-responsive drug release behavior, improved in vitro anti-inflammatory ability, and enhanced accumulation at the site of inflammation in the colon. Furthermore, after oral administration, CNs@EPO@L100 significantly ameliorated the inflammatory symptoms in mice. Taken together, this study provides insights into programmed release through the rational application of pH-sensitive materials and offers strategies for a precisely targeted therapy of UC using core-shell nanoparticles. The nanoparticles were prepared by coating CNs with EPO and L100. After oral, the undesired dissolution of CNs in the stomach and small intestine was reduced due to the L100 and EPO layers, resulting in enhanced availability of CUR at the UC site.