Ligand-Appended BBB-Targeted Nanocarriers (LABTNs)

Delivering therapeutics across the blood brain barrier (BBB) remains the ratelimiting step in brain medicine research. Three main categories of endogenous transportation at BBB that can be used for targeting brain are carrier-mediated transport, active efflux transport, and receptor-mediated transport. Various approaches using nanocarriers such as liposomes, niosomes, micelles, and nanoparticles with manifested surface modifications using either covalent or noncovalent methods to append suitable ligands are being intensively explored to achieve drug delivery to the brain. Harvested ligands include peptide, glutathione, transferrin, and transferrin antibody, lectins, lactic acid, cholera toxin B, etc. In this review, we present recent insights into the development of safe and efficient brain drug delivery as well as recent advances in BBB targeting tactics including antibody-directed enzyme prodrug therapy, a biotin-avidin conjugated system, and chimeric peptides. This review serves as an excellent source of knowledge for budding brain researchers.