Peroral targeting of drug micro or nanocarriers to sites beyond the gastrointestinal tract

摘要: Targeted delivery of drug micro or nanocarriers has been attained via parenteral routes, especially the intravenous route. Conventionally, oral targeting refers to site-specific and triggered release at local sites within gastrointestinal tract (GIT), enteric epithelia through ligand-receptor transporter interactions. Beyond that barrier, concept peroral not clarified. Nevertheless, this is possible as long carriers are able be absorbed into systemic circulation intact. Recent findings on in vivo translocation shed light potential remote beyond GIT. Sequential processes penetration across epithelia, transportation lymphatics ultimate convergence with involved underlying mechanisms. The microfold cell (M cell) pathway plays a leading role breaking epithelial barrier. Accumulating evidence confirms primary series lipid polymeric organs tissues mononuclear phagocyte systems (MPS), such liver, spleen, lungs kidneys. total amount lymph-bound particles could reach 8%, evidenced by quantification glucan microparticles specifically bind M cell. Migration nanocarrier-bearing macrophages attains secondary engulfed distant far MPS. current foresee probability However, content exposure target therapeutic diagnostic promises yet unraveled.