Lipid-polymer nano core-shell type hybrid system for colon specific drug delivery

Site specific drug delivery to the colon provides major advantages to treating diseases associated with the colon, such as inflammatory bowel disease (IBD), diverticulosis, polyps, colorectal cancer etc., A precise colon targeted drug delivery platform is expected to reduce drug side effects and increase the pharmacologic response at the disease site. In this study, we investigated the effect of a sodium alginate coating on solid lipid nanoparticle (SLNPs) surface characteristics, ulcerative colon targetability and drug release patterns. Mesalamine (MES) loaded SLNPs were characterized for particle morphology, particle size, particle surface charge, drug encapsulation efficiency, in vitro drug release and in vivo histopathological studies. Our result showed that the particles were spherical in shape with an average size range of 203 ± 50 nm and a 56–72% encapsulation efficiency. The drug release for alginate coated nanoparticles (F5) was found to be 87.3% in rat caecal medium after 24 h. The current in vitro release studies demonstrate that sodium alginate coated nanoparticles prevented the burst drug release in acidic medium. The therapeutic potential and in vivo efficacy of the present nanoparticles were evaluated in a TNBS induced colitis model. Compared to MES-Suspension treated group, the MES-SLNPs group showed increased body weight and colon length and noticeably decreased colon weight/length ratios, histological damage, and inflammatory cell infiltration in colon tissue. Our RESULTS demonstrated that polysaccharide (sodium alginate) coated nano-hybrid particles are an effective oral colon-targeted delivery system for colitis therapy.