Preparation and characterization of pH-sensitive nanoparticles of budesonide for the treatment of ulcerative colitis

Hong Zhou,1,2 Haixin Qian1 1Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou 215006, People’s Republic of China; 2Department of Gastrointestinal Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, People’s Republic of China Objective: The aim of this study was to develop pH sensitive nanoparticles of budesonide for the treatment of ulcerative colitis.Methods: The NPs system was characterized by the transmission electron microscopy (TEM), particle size, drug loading and encapsulation efficiency. In addition, in vitro drug release properties and pharmacokinetics were also investigated in detail. The optimized formulation was examined for its in-vivo targeting potential using 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in a rat model.Results: Dynamic light-scattering results showed that the particle size of budesonide-Eudragit S100/poly(lactic-co-glycolic acid) nanoparticles was around 110.5 nm, with a polydispersity index of 0.098. Transmission electron microscopy images showed that BUD-ES100/PLGA NPs were spherical with uniform size and relatively smooth surfaces. In vitro release showed that BUD-ES100/PLGA NPs required minimal release of drugs during its transit in the stomach and the upper small intestine to ensure that a maximum dose reached the colon. After the pharmacodynamic treatment, the myeloperoxidase value of BUD-ES100/PLGA NPs was close to the normal group. The histopathological examination of rectum showed that no sign of damages such as epithelial necrosis and sloughing epithelial cells was detected.Conclusion: Our findings suggested that BUD-ES100/PLGA NPs were a promising alternative to single pH-dependent systems for colitis therapy. Keywords: budesonide, nanoparticles, ES100/PLGA, in vitro release, pharmacodynami